/ˈkwɒntə/, U.S. /ˈkwɑn(t)ə/, (rare, chiefly in sense A. 5) quantums.quantumn.adj.
/ˈkwɒntəm/, U.S. /ˈkwɑn(t)əm//ˈkwɒntə/, U.S. /ˈkwɑn(t)ə/, (rare, chiefly in sense A. 5) quantums. A. n.
1. Chiefly Philosophy. Something that has quantity; (sometimes) spec. = quantity n. 3.
ΘΚΠ
the world > relative properties > number > mathematical number or quantity > [noun]
i-telc1000
telc1000
numberc1300
suma1387
quantitya1398
umberc1400
value1543
term1552
terminus?a1560
quantum1567
valuation1636
numerality1646
numeration1646
numerical1760
numeric1878
naturality1942
1567 J. Jewel Def. Apol. Churche Eng. 342 Somme..there be, whiche write, that the Body of Christe in the Sacramente is quantum [1564 that ye body of Christ is quantum in Eucharistia], that is to saie, hath his perfite quantitie in the Sacramente.
1647 H. More Philos. Poems ii. i. ii. lv Each quantum's infinite, straight will be said.
1678 R. Cudworth True Intellect. Syst. Universe i. v. 783 Though it be an Absolute Contradiction, for a Body, or Quantum, to be..All of it in every Part of that Space, which the Whole is in.
c1733 A. Baxter Enq. Nature Human Soul vii. 320 If there is nothing that can be called quantum in nature, or without the mind; nothing to which quantity is applicable; then we have a large body of fine demonstration, and men have discovered vast numbers of eternal and undeniable properties..precisely of nothing.
1877 E. Caird Crit. Acct. Philos. Kant ii. xi. 442 All phenomena, as perceived, are extensive quanta.
1981 Diacritics June 35 Kant recognizes that any use the imagination makes of a quantum received in intuition for the purpose of measuring or estimation cannot proceed exclusively by means of apprehension.
2. † b. = quantity n. 10a. Obsolete.
a. Total amount or quantity; = quantity n. 6. In later use chiefly Law (with reference to amounts of money: cf. quantity n. 6d) and South Asian.
ΘΚΠ
the world > relative properties > quantity > [noun]
metc1225
mountancec1330
amountancec1380
mountenancec1385
quantityc1392
quantitya1398
substance1435
mountenessea1450
mountc1475
number1477
feck1488
quantum1602
valour1631
amount1668
amt.1744
volume1882
society > trade and finance > money > sum of money > [noun]
sumc1300
sumc1300
so muchc1384
quantity1405
sum in gross (also in great)1421
summa?a1425
amount1450
sold1513
bankc1530
quantum1602
cash1677
amt.1744
figure1842
a bit1894
society > law > administration of justice > court proceedings or procedure > action of courts in claims or grievances > claim at law > [noun] > a sum payable in damages
damage1542
quantum1602
ad damnuma1754
solatiuma1859
the world > relative properties > quantity > [noun] > of immaterial things
quantitya1398
quantum1791
1602 ‘A. Philalethes’ Answere Fraudulent Let. G. Blackwels Pref. sig. Aij That..you may peruse and see..the Longum, Latum, & Profundum of this tropicall Rhetoricians capacitie, and by consequent the Quantum of the whole Compositum.
1605 F. Bacon Of Aduancem. Learning ii. f. 21v Is not the obseruation, Omnia mutantur, nil interit, a contemplation in Philosophie thus, that the Quantum of Nature is eternall. View more context for this quotation
1619 S. Purchas Microcosmus xxxii. 302 To set The true Quantum, the true poize and price vpon himselfe.
1732 Gentleman's Mag. July 866/2 As the Quantum of that loss could not then be determin'd.
1749 H. Fielding Tom Jones IV. xi. ix. 176 The Reader will perhaps be curious to know the Quantum of this Present, but we cannot satisfy his Curiosity. View more context for this quotation
1758 G. Gilbert Two Treat. Proc. Equity II. 138 The quantum of such pecuniary legacy is to be ascertained in such sense, according to the intention of the testator.
1791 ‘T. Newte’ Prospects & Observ. Tour 179 The momentum of bodies depends on the quantum of their velocity multiplied into that of their matter.
1855 Amer. Law Reg. 3 539 Varying according to circumstances; for instance, the quantum of the legacy, and the proportion it bears to the property disposed of.
1898 in Southern Reporter 23 718/2 The quantum of damages as fixed by the lower court is, we think, too low.
1912 Law Rep.: Appeal Cases 688 The quantum of damage is a question of fact, and the only guidance the law can give is to lay down general principles.
1956 Far Eastern Q. 15 493 The medium has held good in spite of the vast increase in the quantum of change which has occurred in British and post-British India.
1970 Internat. & Compar. Law Q. 19 126 Strict liability with an unbreakable limit should confine litigation to questions of quantum.
1992 Sunday Observer (Sri Lanka) 6 Sept. (New Delhi ed.) (Life section) p. i/2 The enormous quantum of heroin flowing through Bombay.
ΘΚΠ
the world > space > extension in space > measurable spatial extent > largeness > [noun] > largeness of volume or bulkiness
hugenessc1380
grossnessa1513
quantity1554
greatness1595
bulk1626
voluminousness1664
bulkiness1674
volume1794
quantum1815
1815 W. H. Ireland Scribbleomania 33 His study has not been for quantum to strive, But with beauties to keep the attention alive.
3. Chiefly with possessive adjective. That which is allotted to or expected of a particular person; one's share or portion; a quota, an allocation.
ΘΚΠ
the mind > possession > giving > distributing or dealing out > an allotted share, portion, or part > [noun]
dealc825
lotOE
dolea1225
partc1300
portion?1316
sort1382
parcelc1400
skiftc1400
pane1440
partagec1450
shift1461
skair1511
allotment1528
snapshare1538
share1539
slice1548
fee1573
snap1575
moiety1597
snatch1601
allotterya1616
proportiona1616
symbol1627
dealth1637
quantum1649
cavelc1650
snip1655
sortition1671
snack1683
quota1688
contingency1723
snick1723
contingent1728
whack1785
divvy1872
end1903
bite1925
1649 Bp. J. Taylor Great Exemplar ii. xii. 94 Poverty is her portion, and her quantum is but food and raiment.
1692 T. Goodwin Disc. Christ the Mediator v. vii, in Wks. (1863) V. 222 So they had every one his cup, every one his quantum or portion.
1724 J. Swift Some Observ. Wood's Half-pence 29 He will double his present Quantum by Stealth as soon as he can.
1761 L. Sterne Life Tristram Shandy III. xx. 91 There is but a certain quantum stored up for us all, for the use and behoof of the whole race of mankind.
1818 J. Bentham Church-of-Englandism 421 A Parish, in which the quantum of this soul-saving Mammon rises as high as 12,000l. a year.
1829 P. Egan Boxiana New Ser. II. 690 He received his quantum of punishment.
1897 F. T. Bullen Cruise ‘Cachalot’ 167 Having completed our quantum of wood, water, and fresh provisions.
1946 Times 26 Nov. 5/4 He had to get up at five o'clock in the morning to turn out his quantum of witty paragraphs at sixpence a joke.
1994 Guardian (Nexis) 28 July 22 He also dismisses the slightest claim from Scotland or Wales for their own quantum of decentralised government.
4.
a. The actual amount or quantity of something present, available, etc.; = quantity n. 1c.
ΘΚΠ
the world > relative properties > quantity > [noun] > some, any, or indefinite amount > as related to amount of which it is part > amount or portion present in anything
quantity?1490
quantum1735
content1901
1735 G. Berkeley Querist §215 Such a Bank..was faulty in not limiting the Quantum of Bills.
1762 G. Campbell Diss. Miracles i. vi. 96 Surely if any miracle may be called little, the last above mentioned is intitled to that denomination..because the quantum of miraculous force requisite, is,..ever so little, or the least conceivable.
1806 Edinb. Rev. 8 297 The exact quantum of damage which productive industry must sustain.
1858 Harper's Mag. Apr. 592/1 After the usual quantum of ‘backing and filling’, and shouting and blowing of steam, the vessel was secured alongside the wharf.
1890 E. R. Lankester Advancem. Sci. i. 14 A struggle among all those born for the possession of the small quantum of food.
1973 L. G. Forer in A. E. Wilkerson Rights of Children 31 The procedures by which he was committed or the quantum of care that he received.
1999 Church Times 12 Mar. 20/2 The Church should minimise the quantum of bricks and mortar we have to maintain, as such things consume too much time, energy and money.
b. A specified or definite amount or quantity; = quantity n. 1a.
ΘΚΠ
the world > relative properties > quantity > [noun] > a definite or specified quantity or amount
quantitya1325
measurec1384
certainc1386
certainty1431
assignment1519
dosis1543
dose1607
matter1610
quantum1747
volume1812
1747 C. Chauncy Civil Magistrates Must be Just 38 They are confined to a nominal quantum, which every day varies in its real worth.
1789 W. Belsham Ess. I. ii. 19 Is there not a sufficient quantum of distress and misfortune?
1829 T. Carlyle in Edinb. Rev. June 455 Some smaller quantum of earthly enjoyment.
1852 W. Jerdan Autobiogr. II. xii. 137 Imbued with a moderate quantum of worldly wisdom.
1887 Encycl. Brit. XXII. 624/1 From 50° upwards the solubility increases at such a rate that a given quantum of water dissolves any quantity of sugar if the mixture is constantly kept boiling.
1909 A. A. Brill tr. S. Freud Sel. Papers on Hysteria vi. 136 A quantum of freely floating anxiety which controls the choice of ideas by expectation.
1929 Encycl. Brit. XXII. 960/2 Imputed price..is an estimate of the amount of money for which a given article or a given quantum of goods could be sold or bought.
1987 D. Lindsay Haunted Woman 11 It pleases him to imagine that I possess an average quantum of common sense, on which account he has invited my assistance.
c. Physics. The quantity of electric fluid present in an electrically neutral body. disused.
ΚΠ
1870 Nature 20 Jan. 306/1 On this hypothesis, ‘quantities of electricity’, positive and negative, are excesses of the quantity of the hypothetical fluid above or below the ‘quantum’ corresponding to zero of the electric tests.
1902 Ld. Kelvin in London, Edinb., & Dublin Philos. Mag. 6th Ser. 3 259 The neutralizing quantum of electrions [= ‘atoms of resinous electricity’] for any atom or group of atoms has exactly the same quantity of electricity of one kind as the atom or group of atoms has of electricity of the opposite kind. The quantum for any single atom may be one or two or three or any integral number, and need not be the same for all atoms.
1904 Ld. Kelvin in London, Edinb., & Dublin Philos. Mag. 6th Ser. 7 221 An atom shot from radium with less than its neutralising quantum of electrions cannot go far through a solid or a liquid without acquiring the neutralising quantum.
5. Physics. A minimum amount of a physical quantity which can exist, and in multiples of which it can vary. (Cf. quantum theory n.).
a. A discrete quantity of electromagnetic energy proportional in magnitude to the frequency of the radiation it represents, such that energy of that frequency may only be transmitted in multiples of the quantity.
ΘΚΠ
the world > matter > physics > electromagnetic radiation > [noun] > quantity of
quantum1910
photon1926
the world > matter > physics > quantum theory > [noun] > minimum of physical quantity
quantum1910
quant1918
1910 Sci. Abstr. A. 13 556 The absorption of the corresponding light-quantum.
1913 London, Edinb. & Dublin Philos. Mag. 6th Ser. 26 19 These calculations strongly suggest that an electron of great velocity in passing through an atom and colliding with the electrons bound will loose energy in distinct finite quanta.
1922 J. Mills Within Atom xi. 148 The scientific world has quite unanimously accepted it to be a fact that energy is emitted in quanta.
1929 D. H. Lawrence Pansies 28 Look then Where the father of all things swims in a mist of atoms Electrons and energies, quantums and relativities.
1947 Nucleonics Dec. 22/2 Gamma quanta exceeding these energies may produce neutrons by photodisintegration of these elements.
1965 Physical Rev. Lett. 15 1013/1 He+ ions decaying spontaneously..in ∼1 × 10−8 seconds with the emission of a 1640Å quantum followed by a 303Å quantum.
2002 J. M. Charap Explaining Universe iv. 48 Our refined scientific instruments, and even our eyes, detect individual quanta. Quanta can be counted, one at a time; they can be emitted or absorbed, like particles.
b. More fully quantum of action. = Planck's constant n. at Planck n. 1d.
ΘΚΠ
the world > matter > physics > electromagnetic radiation > [noun] > quantity of > Planck's constant
H1901
Planck's constant1910
quantum of action1913
Planck's quantum1914
1913 London, Edinb. & Dublin Philos. Mag. 6th Ser. 26 2 Whatever the alteration in the laws of motion of the electrons may be, it seems necessary to introduce..a quantity foreign to the classical electrodynamics, i.e. Planck's constant, or as it often is called the elementary quantum of action.
1922 Rep. Brit. Assoc. Advancem. Sci. 1921 473 The essential feature of the [quantum] theory is the existence of a universal constant, the quantum h = 6·55 × 10−27 erg sec., which in some way..controls exchanges of energy.
1933 Nature 25 Mar. 422/2 A causal description in the classical sense is possible only in such cases where the action involved is large compared with the quantum of action.
1956 E. H. Hutten Lang. Mod. Physics v. 179 We can measure simultaneous values of both parameters only in such a way that the numerical product of their inaccuracies is, at best, equal to the quantum of action h.
2004 C. Norris Philos. of Lang. v. 118 This is not to say that Planck's quantum of action h necessarily marks the advent of a new and unprecedented stage in the evolution of physics.
c. A discrete amount of any other physical quantity (such as momentum or electric charge) analogous to that of electromagnetic energy (sense A. 5a).
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > minimum of physical quantity > of electric charge
quantum1914
1914 Chem. Abstr. 8 1050 (heading) Existence of quantities of electricity which are smaller than the charge of the elementary quantum or the electron.
1923 H. L. Brose tr. A. J. W. Sommerfeld Atomic Struct. & Spectral Lines iv. 199 The rotator is to be quantised not in energy quanta but in quanta of moment of momentum.
1931 H. P. Robertson tr. H. Weyl Theory of Groups & Quantum Mech. i. 43 The elementary quantum of electric charge e.
1958 Nature 31 May 1524/1 (heading) Detection of single quanta of circulation in rotating helium II.
1974 H. E. Hall Solid State Physics ii. 67 It is often convenient to treat lattice vibrations in an analogous way, and introduce the idea of phonons of energy ħω as quanta of excitation of the lattice.
1988 J. D. Barrow & F. J. Tipler Anthropic Cosmol. Princ. (rev. ed.) v. 298 The emission of photons is inhibited..because they must always carry away whole quanta of angular momentum.
2004 Sci. Amer. (U.K. ed.) May 32/1 Today's leading candidate for a full quantum theory of gravity—string theory—introduces a minimal quantum of length.
d. figurative and in extended use: a small discrete amount of something. Frequently in plural.
ΘΚΠ
the world > relative properties > quantity > smallness of quantity, amount, or degree > [noun] > least quantity or amount > least amount to change quantity
quantum1944
1944 L. Mumford Condition of Man vii. 247 Now, every new quantum of accurate knowledge was precious.
1960 R. W. Marks Dymaxion World Buckminster Fuller 10/1 All experiments performed, books written, thoughts expressed, and structures completed, are finite energy events. Together they form a totality, a cornucopia of patterned quanta.
1969 Daily Tel. 10 Jan. (Colour Suppl.) 32/2 Generalisations serve a purpose, but true understanding is made up of many discrete quanta.
1998 N.Y. Times (Nexis) 24 May 14/2 The brilliant bits of interwoven color, each of which (like a good painter's brush stroke) bears its own quantum of intense sensation.
6. Physiology. Originally: a small voltage of which integral multiples go to make up the end-plate potential measured at a neuromuscular junction. Later also: a unit amount of neurotransmitter that corresponds to such a voltage or is released from a single synaptic vesicle.
ΘΚΠ
the world > life > biology > laboratory analysis > measure > [noun] > unit
international unit1857
microunit1900
morgan1919
megaunit1920
S1942
Svedberg unit1942
quantum1952
Somogyi unit1956
cistron1957
1952 P. Fatt & B. Katz in Jrnl. Physiol. 117 120 The experiment throws some new light on the action of calcium at the nerve-muscle junction: lack of calcium apparently reduces the e.p.p. in definite ‘quanta’.
1954 J. del Castillo & B. Katz in Jrnl. Physiol. 124 574 Recent evidence indicating that ACh release occurs in discrete quanta.
1970 J. W. Phillis Pharmacol. of Synapses ii. 17 In addition to being released by stimulation, individual quanta are released from the terminal spontaneously... At the neuromuscular junction, the number of quanta available for immediate release is probably of the order of 1000.
1984 J. F. Lamb et al. Essent. Physiol. (ed. 2) ii. 39 At present it is thought that the spontaneous release of quanta keep the muscle cells ‘normal’ by a mechanism which is not understood.
2003 Science 11 July 145/1 Resting neurons release the contents of individual synaptic vesicles spontaneously and at random intervals. The ensuing miniature postsynaptic potentials..correspond to individual quanta of the postsynaptic response.
B. adj. (chiefly attributive).
Physics. Involving or relating to quanta or quantum theory. Cf. quantal adj. 2c.
ΘΚΠ
the world > matter > physics > quantum theory > [adjective]
quantum-theoretical1920
quantum1924
quantal1936
1924 Physical Rev. 24 340 This connection of the classical and quantum differential absorption we shall term the correspondence principle for absorption.
1951 Physical Rev. 82 116/2 The quantum nature of the exchange of energy between free electrons and electromagnetic fields.
1975 Nature 20 Mar. 223/3 The book is concerned mainly with electro~dynamics (both classical and quantum).
1989 New Scientist 15 July 69/4 Conrad Schneiker..discusses the possibilities for implementing computation that is intrinsically quantum.
1994 H. R. Glyde Excitations in Liquid & Solid Helium i. 2 Solid helium is the most quantum solid readily available in nature.
2004 K. Nakamura & T. Harayama Quantum Chaos & Quantum Dots i. 10 The semiclassical theory serves as a dictionary in our translating the language of the classical world into that of the quantum one.
Compounds
C1. (In sense A. 5.)
quantum computation n.
ΚΠ
1989 Proc. Royal Soc. A. 425 90 The existence of a universal quantum gate simplifies the theory of quantum computational networks and of quantum computation generally.
1998 Computer Weekly 19 Mar. 48/2 The most famous candidate for quantum computation, though, is factoring.
quantum effect n.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > application of quantum theory > effect attributed to quantum
quantum effect1914
1914 Chem. Abstr. 8 3141 A small quantum effect is apparent.
1946 Physical Rev. 69 195 (heading) Quantum effects in the interaction of electrons with high frequency fields and the transition to classical theory.
2004 B. Bunch & A. Hellemans Hist. Sci. & Technol. 632/3 There is..much talk about the future of quantum computers, machines that would use quantum effects to process information.
quantum energy n.
ΚΠ
1913 Proc. Royal Soc. A. 89 247 The quantum energies should be proportional to the frequencies.
1921 Discovery Sept. 227/2 When the quantum energy of the exciting radiation exceeds this amount the whole K series [of X-rays] is excited.
2001 R. W. Cahn Coming of Materials Sci. vi. 228 An ‘energy-dispersive’ analyser..uses a scintillation detector with an electronic circuit to determine the quantum energy of the signal.
quantum hypothesis n.
ΚΠ
1913 Science 24 Jan. 130/2 The..most concentrated form of quantum hypothesis..was proposed by Einstein in 1905.
1988 S. W. Hawking Brief Hist. Time (BNC) 56 Although light is made up of waves, Planck's quantum hypothesis tells us that in some ways it behaves as if it were composed of particles.
quantum law n.
ΚΠ
1916 Chem. Abstr. 10 1722 (heading) The quantum law and the structure of the hydrogen atom.
1967 E. U. Condon & H. Odishaw Handbk. Physics (ed. 2) vii. i. 3/1 The quantum laws must go over asymptotically into the classical laws..as the scale of the phenomena is increased.
2003 B. Bryson Short Hist. Nearly Everything (2004) xi. 213 By introducing extra dimensions, superstring theory enables physicists to pull together quantum laws and gravitational ones into one comparatively tidy package.
quantum phenomenon n.
ΚΠ
1920 Proc. National Acad. Sci. U.S.A. 6 122 This numerical coincidence suggests that quantum phenomena may be in some way connected with rotating electric fields.
2002 J. Cohen & I. Stewart Evolving Alien x. 232 Roger Penrose argues that human consciousness stems from quantum phenomena in tubulin molecules—long tubes of protein units that could act as waveguides.
quantum physicist n.
ΚΠ
1930 Proc. National Acad. Sci. U.S.A. 16 426 One may hope for a probability interpretation of mechanics via these processes—a desirable result from the point of view of the quantum physicist.
1964 M. McLuhan Understanding Media (1967) vii. 73 Werner Heisenberg..is an example of the new quantum physicist whose over-all awareness of forms suggests to him that we would do well to stand aside from most of them.
1992 Independent 14 Sept. 14/1 Known to quantum physicists as a ‘Squid’, the device lies at the heart of a magnetometer, an instrument that builds up an image of the brain at work.
quantum physics n.
ΚΠ
1928 Science 31 Aug. 193/2 The fundamental fact for quantum physics..is a double duality of wave and particle concepts.
1971 Sci. Amer. Mar. 75 Quantum physics normally deals with natural phenomena on a submicroscopic scale.
1999 Guardian 4 Dec. (Saturday section) 10/6 Science is again central: this time, the theoretical possibility raised by quantum physics that teletransportation (time travel) might be possible.
quantum property n.
ΚΠ
1927 A. S. Eddington Stars & Atoms 68 The property here referred to (the quantum property) is the deepest mystery of light.
1978 Nature 16 Mar. 291/3 The quantum properties of electromagnetic radiation.
2004 New Scientist 20 Nov. 18/1 The quantum property of spin makes electrons act like magnets.
C2. Chiefly Physics and Electronics.
quantum bit n. (in a quantum computer) a physical system for storing information that is capable of existing in either of two quantum states or in a superposition of both (e.g. a spinning particle), and hence can represent two different binary values simultaneously; a unit of information held in this way; also called qubit.
ΚΠ
1991 G. Brassard & C. Crépeau in A. J. Menezes & S. A. Vanstone Adv. in Cryptology 49 The first quantum bit commitment scheme ever proposed is due to Bennet and Brassard..(actually, the protocol they describe is only claimed to implement coin tossing, but it is obvious how to modify it in order to implement bit commitment).
1994 Computing 28 July 38/6 To take advantage of any increase in information capacity, the messages would be encoded in particles in a range of quantum states, each having independent probabilities. These quantum bits—‘qubits’—should allow an increase in data compression in certain coding regimes.
1999 Sci. Amer. Aug. 14/3 Some labs have even built working models of quantum bits..using ions trapped in special cavities or nuclear magnetic resonance techniques.
quantum-chemical adj. of or relating to quantum chemistry.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [adjective] > relating to quantum chemistry
quantum-chemical1953
1953 Proc. Royal Soc. A. 216 p. vii His ideas are at the very basis of quantum chemical theory.
1960 McGraw-Hill Encycl. Sci. & Technol. XI. 145/2 The most useful of these methods, the variation method, has produced most of the important quantum-chemical concepts.
1992 Chem. in Brit. (BNC) 28 140 Here the quantum chemical theory of bonding has had some remarkable successes.
quantum chemist n. an expert or specialist in quantum chemistry.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [noun] > quantum chemistry > expert in
quantum chemist1957
1957 Jrnl. Physical Chem. 61 68/1 Quantum chemists..know several ways of solving the many-electron Schrödinger equation in principle.
1970 Sci. Amer. Apr. 54/1 Since the introduction of the fundamental wave equation of quantum mechanics by Erwin Schrödinger in 1926, much of the work of quantum chemists has been focused on its solution for specific chemical systems.
1992 Chem. in Brit. (BNC) 28 138 The quantum chemists have remained patient and undaunted.
quantum chemistry n. [after German Quantenchemie (1929 or earlier)] the branch of physical chemistry concerned with the explanation of chemical phenomena in terms of quantum mechanics.
ΘΚΠ
the world > matter > chemistry > chemistry as a science > branches of chemistry > [noun]
physical chemistry1743
zymology1753
pneumatic chemistry1788
stoicheiometry1807
electrochemistry1811
phytochemistry1837
thermochemistry1844
actinochemistry1845
inorganic chemistry1847
phytochimy1847
biochemistry1848
microchemistry1853
palaeochemistry1854
actinology1855
photochemistry1860
physico-chemistry1860
zymotechny1860
anorganology1876
kinetics1884
structural chemistry1884
stereochemistry1890
spectrochemistry1893
cytochemistry1900
radiochemistry1904
immunochemistry1907
magnetochemistry1914
leptonology1917
surface chemistry1919
crystal chemistry1921
radiation chemistry1926
leptology1928
mechanochemistry1928
agrochemistry1930
sonochemistry1934
quantum chemistry1938
cosmochemistry1940
polymer chemistry1945
conductometry1946
topochemistry1948
proto-chemistry1962
stereology1963
biochem1968
femtochemistry1988
combinatorial chemistry1992
cheminformatics1996
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [noun] > quantum chemistry
quantum chemistry1938
1938 Jrnl. Amer. Chem. Soc. 60 734/2 Einführung in die Quantenchemie. (Introduction to Quantum Chemistry.) By Dr. Hans Hellmann.
1963 New Scientist 14 Mar. 582/3 After a rather long incubation period, the new subject of ‘quantum chemistry’ has got into its stride and is gaining rapidly in strength.
1998 New Scientist 25 July 6/3 Lidar's algorithm is one of a growing number designed for quantum computers, and is thought to be the first in the field of quantum chemistry.
quantum chromodynamics n. [after quantum electrodynamics n.] a quantum field theory in which the strong interaction is described in terms of an interaction between quarks that is mediated by gluons, both kinds of particle being assigned a quantum number called ‘colour’; abbreviated QCD.
ΘΚΠ
the world > matter > physics > atomic physics > particle physics > quark > [noun] > quantum chromodynamics
QCD1975
quantum chromodynamics1975
chromodynamics1976
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [noun] > quantum chromodynamics
QCD1975
quantum chromodynamics1975
1975 H. Fritzsch et al. in Physics Lett. B. 59 256/1 A good name for this theory is quantum chromodynamics (QCD).
1992 Guardian 27 Oct. ii. 11/1 [Feynman] was much interested in the field mystically referred to as quantum chromodynamics—the study of quarks, gluons, strange particles and the like.
1999 D. Mitchell Ghostwritten 331 I can't make heads or tails of your matrix mechanics, your quantum chromodynamics, and your nothing turning into something by energy borrowed from nowhere.
quantum computer n. an (originally hypothetical) computer in which information is represented in terms of the possible quantum states of a set of physical systems.
ΚΠ
1982 Internat. Jrnl. Theoret. Physics 21 474 Let the computer itself be built of quantum mechanical elements which obey quantum mechanical laws... A new kind of computer—a quantum computer.
1985 Proc. Royal Soc. A. 400 97 Computing machines resembling the universal quantum computer could, in principle, be built and would have many remarkable properties not reproducible by any Turing machine.
1998 Pop. Sci. Mar. 67/3 (caption) A team at Los Alamos National Laboratory is working on a prototype quantum computer using an ‘ion trap’ device in which the electrons of suspended calcium ions are acted upon by lasers.
2022 N.Y. Times (Nexis) 26 May b6 Most experts believe several more years will pass—at the very least—before a quantum computer can actually do something useful that you cannot do with another machine.
quantum computing n. the action or practice of using the quantum states of subatomic particles to store and process information; the use of quantum computers.
ΚΠ
1985 Proc. Royal Soc. A. 400 97 Quantum computing machines, and indeed classical stochastic computing machines, do not ‘compute functions’ in the above sense.
1997 Sun (Baltimore) (Nexis) 13 May 11 a Computer experts talk excitedly about the possibility of ‘quantum computing’ in which a single atom might perform switching operations—so huge amounts of data could be stored on the head of a pin.
2021 Times (Nexis) 23 Apr. 12 Britain must adapt by developing sovereign technologies in key areas such as quantum computing and cryptology to protect the most sensitive information and capabilities.
quantum condition n. a condition resulting from, or forming part of, the application of quantum theory to a system; a condition that selects from the states allowed by classical physics those that are consistent with quantum theory.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > condition consistent with
quantum condition1920
1920 Science 18 June 607/1 By imposing the quantum condition that the angular momentum of each electron at the mid-point of its path shall be h/ 2π, it becomes possible to calculate the radius vector and the velocity.
1955 O. Klein in W. Pauli Niels Bohr & Devel. Physics 99 The importance of transformation groups for the formulation of quantum conditions in field theories..has been strongly emphasized.
1998 N. Maxwell Comprehensibility of Universe viii. 248 We seek some elemental quantum condition for the occurrence of probabilistic events.
quantum cryptography n. a technique for the encryption of transmitted information which uses quantum properties (typically the polarization or the entanglement of photons) to construct shared random cryptographic keys in such a way that any interception of the communication channel is revealed by the disturbance it causes to the quantum system.
ΚΠ
1983 C. H. Bennett et al. in D. Chaum et al. Adv. in Cryptol. (Proc. CRYPTO '82) 267 (heading) Quantum cryptography, or unforgeable subway tokens.
1992 Sci. Amer. Oct. 33/3 If its mathematical efficiency can be sufficently improved, discreet decision making may become the most important application of quantum cryptography.
2004 New Scientist 15 May 19/1 For the first time, quantum cryptography can create unbreakable encryption fast enough to protect applications as data-hungry as video streaming.
quantum defect n. a number representing the degree to which an energy level of an atom with a single valence electron is displaced relative to the corresponding level of the hydrogen atom, being the amount by which the actual principal quantum number of the level exceeds the effective value of the number.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > quantum number
quantum number1902
quantum defect1915
principal quantum number1922
magnetic quantum number1923
1915 Astrophysical Jrnl. 61 67 Theoretically, the ‘residual’ or ‘quantum defect’ should always be negative.
1970 G. K. Woodgate Elem. Atomic Struct. vi. 105 We consider the sequence iso-electronic with sodium... The ionization potentials for this sequence..together with the quantum defect δ(s)..are given below.
2003 B. M. Smirnov Physics of Atoms & Ions vi. 157 The quantum defect decreases strongly with an increase in the electronic orbital momentum l, because the higher the electronic orbital momentum, the less the probability for the electron to locate near the atomic core.
quantum dot n. a semiconductor crystal of nanometre dimensions in which electrons, holes, or excitons are confined to a region comparable in size to their wavelength (effectively, to a point), leading to their having quantized energy levels as in an atom.
ΚΠ
1985 Science 19 Apr. 315 [They] have made what they call quantum dots, which are the first manmade objects to show spatial quantization in three dimensions.
2000 Nature 27 Apr. 920/2 Awschalom's team has also succeeded in trapping coherent spin packets in semiconductor ‘quantum dots’—crystals of cadmium selenide between 2 and 8 nanometres across.
2004 BusinessWeek 1 Mar. 115/3 Scientists are already thinking about adding drugs to the quantum dots to create ‘smart bombs’ that can be tracked as they target cancer cells.
quantum-dynamical adj. of or relating to quantum dynamics; quantum-mechanical.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > [adjective]
quantum-mechanical1927
quantum-dynamical1928
1928 Proc. National Acad. Sci. U.S.A. 14 185 If the quantum dynamical system is one which has a ‘discrete’ rather than entirely continuous matrix spectrum; [etc.].
2000 Science 3 Nov. 961/1 A full quantum dynamical study of the reactions of a hydrogen atom with water..is reported.
quantum dynamics n. = quantum mechanics n.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > [noun]
quantum dynamics1921
quantum mechanics1922
1921 Proc. Royal Soc. A. 99 270 It is probable that the quantum dynamics holds for that part of the atom from which these ɣ-rays come.
1930 J. H. Jeans Universe around Us (ed. 2) ii. 129 The general concepts of quantum-dynamics prohibit the electron from moving in all these orbits indiscriminately.
1967 E. U. Condon & H. Odishaw Handbk. Physics (ed. 2) vii. i. 3/1 These laws of quantum dynamics must involve the universal Planck constant..in an essential way.
2000 Jrnl. Econ. Lit. 38 1099/1 An analysis of quantum dynamics and related problems in probability theory.
quantum efficiency n. the proportion of incident photons that are effective in causing the photodecomposition of a molecule, the emission of a photoelectron, or a similar photoeffect.
ΘΚΠ
the world > matter > physics > atomic physics > particle physics > apparatus for detecting charged particles > [noun] > effective proportion of photons
quantum efficiency1926
quantum yield1927
1926 Trans. Faraday Soc. 21 453 In the photochemical isomeric change of maleic and fumaric acid, the quantum efficiency was found to be much smaller than unity.
1953 G. E. Fogg Metabolism of Algae ii. 31 Certain substances..stabilize adapted algae against de-adaptation in the light,..but at the same time reduce the quantum efficiency of the process.
1998 Sky & Telescope Mar. 11/1 (advt.) The AP7 incorporates..CCDs to give it the highest quantum efficiency of any camera in its price range.
quantum-electrodynamic adj. of or relating to quantum electrodynamics.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum electrodynamics > [adjective]
quantum-electrodynamical1934
quantum-electrodynamic1949
1949 Proc. Physical Soc. A. 62 783 The development of a quantum electrodynamic theory for a finite electron might lead to a different result.
1956 Proc. Royal Soc. A. 234 516 The quantum-electrodynamic formula for the shift of S states is [etc.].
2001 B. K. Ridley On Science vii. 121 Quantum electrodynamic shifts in the energy of the electron in a hydrogen atom could be calculated to an impressive precision.
quantum-electrodynamical adj. = quantum-electrodynamic adj.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum electrodynamics > [adjective]
quantum-electrodynamical1934
quantum-electrodynamic1949
1934 Philos. Sci. 1 255 It appears to the writer that the present state of the quantum electrodynamical theories of Physics is in a situation which has a close parallel to optical theories just before 1905.
1996 Austral. Jrnl. Physics 49 489 These calculations have used Heisenberg atomic operators in the quantum electrodynamical model that was developed by Farrell et al.
quantum electrodynamics n. the branch of quantum field theory concerned with the electromagnetic field and its interaction with electrically charged particles; abbreviated QED.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum electrodynamics > [noun]
quantum electrodynamics1927
QED1969
1927 Proc. Royal Soc. A. 114 243 Hardly anything has been done up to the present on quantum electrodynamics.
1971 Sci. Amer. June 64/3 The laws of electricity and magnetism..embodied in the equations of quantum electrodynamics represent the one and only area in physics where a single quantitative description has proved valid over the entire range of experiments for which it has been tested.
1997 Economist 1 Feb. 106/1 A branch of quantum theory known as quantum electrodynamics ( qed) says that a vacuum, far from being static or empty, teems with transient ‘virtual’ particles..that keep popping weirdly into existence and then disappearing again.
quantum-electronic adj. relating to electronic properties as described or explained by quantum theory (rare);of or relating to quantum electronics.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [adjective] > relating to quantum electronics
quantum-electronic1934
1934 Math. Gaz. 18 298 Professor R. H. Fowler opened a discussion on the new quantum electronic theory of metals, which was initiated by Sommerfeld about 1927.
1963 Science 27 Sept. 1247/1 The terms laser and maser are interchangeably used to describe new quantum electronic devices which generate coherent electromagnetic radiation.
1976 B. Bova Multiple Man (1977) i. 11 The President..was protected by an invisible laser-activated shield... Fool-proof quantum-electronic security.
2006 Chem. Physics 322 108 The evolution and decay of quantum electronic coherence in many-body systems.
quantum electronics n. the branch of physics concerned with the practical consequences of the quantization of energy states and their interaction with electromagnetic radiation, and esp. with the production or amplification of microwaves in crystals.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [noun] > quantum electronics
quantum electronics1959
1959 Jrnl. Appl. Physics 30 956/1 An international conference on Quantum Electronics—Resonance Phenomena will be held..on September 14–16, 1959. The conference will consider basic problems in physics and electronics which are important to the increasing use of molecular and atomic resonance in masers, atomic clocks, and related devices.
1972 Physics Bull. Sept. 562/1 Quantum electronics as a field of study dates from the use of stimulated emission for microwave amplification in 1954.
1989 P. Knight in P. Davies New Physics x. 315/2 Quantum electronics (in which the quantum optical physics we have described are utilised in practical devices).
quantum field theory n. a field theory that incorporates or makes use of quantum mechanics, used to describe the properties, behaviour, and interactions of subatomic particles.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > quantum field theory > [noun]
quantum field theory1938
1938 Proc. Royal Soc. A. 166 148 All forms of quantum field theory formulated up to now give such divergencies, as soon as the calculations involve the process of virtual emission and reabsorption of a quantum by one and the same particle.
1978 Sci. Amer. Feb. 128/1 (caption) The creation and annihilation of particles and antiparticles is the characteristic process that distinguishes quantum field theories from ‘classical’ field theories such as Maxwell's or Einstein's.
1996 Focus Apr. 68/4 A bottomless reservoir of energy predicted to exist by quantum field theory (QFT), the laws governing the interaction of electrons and light.
quantum fluctuation n. a short-lived variation in the amount of energy at a point in space occurring as a result of the uncertainty principle, which allows the law of the conservation of energy to be temporarily violated and very short-lived particles to be spontaneously created and annihilated.
ΚΠ
1959 M. Bunge Metascientific Queries Index 274 Collision,..quantum fluctuations due to.
1962 Science 9 Nov. 654/1 Associated with the [electromagnetic] waves, through quantum fluctuation effects, there are particles, the photons, having zero rest mass.
1997 J. Updike Toward End of Time 34 Everything is nothing. The cosmos is a free lunch, a quantum fluctuation.
2001 S. Hawking Universe in Nutshell v. 138 We consider matter to behave according to quantum theory, with uncertainty and quantum fluctuations, but spacetime to be well defined and classical.
quantum gravity n. quantum effects and gravity regarded as manifestations of a single phenomenon; the branch of physics concerned with formulating a theory of this, combining quantum mechanics and the theory of general relativity.
ΚΠ
1970 Physical Rev. D. 2 272 (title) Elementary model for quantum gravity.
1977 P. C. W. Davies Space & Time Mod. Universe v. 166 Although it is not possible to continue known physics back..before the onset of quantum gravity at 10−43 second, it is possible to construct a model of the universe after the first microsecond or so.
1988 M. J. Rees in A. C. Fabian Origins i. 23 Physics is incomplete and conceptually unsatisfactory in that we lack an adequate theory of quantum gravity.
2001 S. Hawking Universe in Nutshell ii. 43 Our classical region of spacetime is bounded to the past, and possibly to the future, by regions in which quantum gravity is important.
quantum level n. an energy level in a quantized system.
ΘΚΠ
the world > matter > physics > quantum theory > electron shell > [noun] > energy level in quantized system
quantum level1924
1924 Proc. Royal Soc. A. 105 186 There is good evidence for the existence of quantum levels in the radium B nucleus.
1960 B. Chalmers & A. G. Quarrell Physical Exam. Metals (ed. 2) xvi. 751 Above the true quantum levels there are further, ‘empty’ levels, representing states in which nuclei may exist momentarily before disintegrating.
1990 New Scientist 28 July 53/1 The zero-point energy perturbs slightly the spectra of lines from transitions between quantum levels in atoms.
quantum liquid n. a liquid that exhibits quantum effects on the macroscopic scale.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > application of quantum theory > effect attributed to quantum > liquid exhibiting
quantum liquid1940
1940 Rep. Progress Physics 7 91 The exponent n is 4 for a solid, and probably also for a ‘quantum liquid’ of the helium type, and 2 for a Fermi gas.
1950 F. London Superfluids I. 1 The ‘superfluids’ or ‘quantum liquids’ probably exhibit the most conspicuous phenomena of macroscopic physics which have not yet been integrated into molecular theory.
1993 Sci. News 16 Jan. 40/2 White dwarfs eventually become quantum crystals, with characteristics quite different from ordinary crystals. ‘And they freeze from something that is actually a quantum liquid.’
quantum logic n. a three-valued logic for dealing with the observation and measurement of quantum phenomena (where simultaneous precise measurement of related variables is not necessarily possible), in which the distributive law of Boolean logic (that p and (q or r) implies (p and q) or (p and r)) does not hold.
ΚΠ
1938 Jrnl. Symbolic Logic 3 117 The quantum logic of Birkhoff and von Neumann.
1986 J. T. Fraser in J. T. Fraser et al. Time, Sci. & Society in China & West i. 15 The extension of physical science into the domain of particles where discrete mathematics had to replace calculus, and quantum logic had to replace classical logic.
1995 Sci. Amer. Oct. 47/3 The result is a quantum logic gate: one photon bit can be flipped partway when another photon reads 1.
quantum-logical adj. of or relating to quantum logic.
ΚΠ
1971 Philos. Sci. 38 511 The quantum-logical operations are not defined truth-functionally, as in standard and even Reichenbachean (three-valued) logic.
1984 A. Comfort Reality & Empathy ii. 124 Computer systems have been selected and designed to copy normal middle-order logic models, not quantum logical models.
2000 Proc. Royal Soc. A. 456 2104 One can..view the nonexistence of truth functions as an argument for a quantum-logical conception of a system's properties.
quantum orbit n. [after German Quantenbahn (1922 in the passage translated in quot. 1923)] an orbit (of an electron in an atom) defined by a set of quantum numbers.
ΘΚΠ
the world > matter > physics > quantum theory > electron shell > [noun] > orbit of electron in atom
quantum orbit1923
1920 Science 5 Nov. 435/1 A two-quantum orbit of an electron in an atom may have both quanta in the form of angular momentum,..or there may be one quantum of angular and one of radial momentum.]
1923 H. L. Brose tr. A. J. W. Sommerfeld Atomic Struct. & Spectral Lines ii. 67 The quantum theory asserts that all these quantum orbits [Ger. Quantenbahnen] are stationary states of motion, that is that they are traversed without radiation being emitted.
2005 Ann. Physics 319 438 We want to investigate how the quantum orbits..can transit continuously to the classical conical orbits.
quantum solid n. a solid that exhibits quantum effects on the macroscopic scale.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > application of quantum theory > effect attributed to quantum > solid exhibiting
quantum solid1967
1967 Science 10 Mar. 1295/3 Dynamics of quantum solids and liquids.
1972 McGraw-Hill Yearbk. Sci. & Technol. 1971 350/1 The interesting properties of the quantum solids are a consequence of their large zero-point motion.
1998 M. Kaku Visions iv. 83 Like the quantum solid which minimizes its energy, a neural network circuit must also minimize its ‘energy’.
quantum state n. a state of a physical (esp. atomic) system that is defined by a set of quantum numbers; a quantized state.
ΘΚΠ
the world > matter > physics > quantum theory > [noun] > application of quantum theory > quantized state
quantum state1921
1921 Science 25 Mar. 291/1 In these equations..n is an integer denoting the quantum state of the electron.
1972 Sci. Amer. Oct. 101/1 The individual nucleons move in discrete quantum states just as the electrons in the atom exist in discrete quantum states.
1990 J. Gribbin & M. Rees Cosmic Coincidences (1991) xi. 274 In the quantum world, as soon as we stop looking at an electron, it dissolves into a mist of probabilities, called a superposition of quantum states.
quantum-statistical adj. of or relating to quantum statistics.
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > [adjective] > relating to quantum statistics
quantum-statistical1929
1929 Science 12 July 41/2 He has done a great service in writing a quantum statistical mechanics more comprehensive than the existing books.
1958 Physical Rev. 111 1460 (heading) Quantum statistical theory of electron correlation.
1996 Progress Theoret. Physics 96 378 Estimate the quantum-statistical averaged radius of the bubble.
quantum statistics n. the statistics of the energy distribution of particles when the quantization of energy is taken into account; cf. Bose–Einstein statistics n. at Bose–Einstein n. 1, Fermi-Dirac statistics n. at Fermi-Dirac n. a
ΘΚΠ
the world > matter > physics > quantum theory > quantum mechanics > [noun] > statistics of energy distribution
statistics1882
quantum statistics1921
Maxwell–Boltzmann statistics1948
1921 Proc. Royal Soc. A. 99 142 Einstein considers the emission and absorption of radiant energy from the standpoint of quantum-statistics.
1972 Physics Bull. Dec. 709/1 It is our great good fortune that the only two substances that remain liquid down to the absolute zero obey different statistics (3He: Fermi–Dirac, 4He: Bose–Einstein) and thus allow us to study the differing effects of quantum statistics on condensed matter.
2002 Brit. Jrnl. Hist. Sci. 35 192 Fowler was an early proponent of the application of quantum statistics to the study of gases in stars.
quantum supremacy n. the demonstrable ability of a quantum computer to solve a problem that a classical computer could not solve in a realistic amount of time.
ΚΠ
2012 J. Preskill in arXiv.org 26 Mar. (arXiv: 1203.5813v1 [quant-ph]) (preprint, accessed 9 Dec. 2021) One way to achieve such ‘quantum supremacy’ would be to run an algorithm on a quantum computer which solves a problem with a super-polynomial speedup relative to classical computers, but there may be other ways that can be achieved sooner, such as simulating exotic quantum states of strongly correlated matter.
2021 Telegraph (Nexis) 3 Dec. 2 A group of physicists..said they had reached ‘quantum supremacy’ in 2019—the Eureka moment at which..[the] experimental machine could outperform today's most powerful supercomputers at a particular function.
quantum teleportation n. a method of transferring a given quantum state from one particle to another by means of entanglement (entanglement n. Additions); = teleportation n. 2.Quantum teleportation is typically achieved by entangling the particle whose quantum state is to be transferred with one of a pair of already entangled particles in such a way that the remaining particle adopts that quantum state.
ΚΠ
1993 C. H. Bennett et al. in Physical Rev. Lett. 70 1898/1 Although it is currently unfeasible to store separated EPR particles for more than a brief time, if it becomes feasible to do so, quantum teleportation could be quite useful.
1997 Indianapolis Star 11 Dec. a15/1 The work is the first to demonstrate ‘quantum teleportation’, a bizarre shifting of physical characteristics between nature's tiniest particles, no matter how far apart they are.
2004 B. Bunch & A. Hellemans Hist. Sci. & Technol. 702/2 This is accomplished through the entanglement of two particles so that measuring the exact quantum state on one instantly determines the state of the other no matter where it may be in the universe. The process is named quantum teleportation.
quantum transition n. = quantum jump n. 1.
ΘΚΠ
the world > matter > physics > quantum theory > electron shell > [noun] > charge of quantized state > abrupt
quantum transition1923
quantum jump1924
quantum leap1930
1923 Proc. National Acad. Sci. U.S.A. 9 242 The probability of a quantum transition associated with the angle θ is proportional to [etc.].
2000 Science 6 Oct. 123/1 We can determine the size of the matrix element that governs the quantum transition of an electron as it tunnels from a state in the emitter layer.
quantum vacuum n. a state devoid of ordinary matter in which virtual particle–antiparticle pairs are continually created and annihilated through quantum fluctuations.
ΚΠ
1975 Physical Rev. D. 11 3370 (title) Quantum vacuum energy in general relativity.
1994 P. Davies Last Three Minutes iii. 35 A by-product of the release of the vacuum energy is that many virtual particles in the quantum vacuum receive some of it and get promoted to real particlehood.
2004 A. Crumey Mobius Dick (2005) 174 ‘The process arises from the Casimir effect,’ said Don. ‘We're effectively harnessing the energy of the quantum vacuum between the reflecting plates.’
quantum well n. a potential well in which electrons and holes are constrained to move in two dimensions only, typically by sandwiching an atomic layer of a semiconductor between layers of a material with a wider band gap, leading to a sharper density of states than in the bulk semiconductor; frequently attributive.
ΚΠ
1978 Appl. Physics Lett. 32 295/2 This is the first report of injection laser operation associated with quantum-well states in Ga(1−x)Alx-GaAs DH [= double-heterostructure] lasers with single-quantum-well active layers.
1993 C. H. Henry in P. S. Zory Quantum Well Lasers 2 The ability to vary the lasing wavelength merely by changing the width of the quantum well.
2000 Wu Yingjian in P. Conceição et al. Sci., Technol. & Innovation Policy xxvi. 423 They are now able to produce different wavelength and multipurpose quantum well semiconductor lasers.
quantum wire n. Physics a wire-like piece of semiconductor in which the movement of electrons is restricted to one dimension, and quantum effects cause their energy of transverse motion (and hence the wire's resistance) to be quantized.
ΚΠ
1984 Jrnl. Luminescence 29 137 A theoretical treatment of the scattering time T in two dimensionally confined GaAs—so-called quantum well wires—predicts a substantial increase in scattering time T..provided all impurities outside the wire have an equal distance to the quantum wire.
1994 Sci. Amer. June 10/1 Now that we finally have a quantum wire laser..we can measure whether it has useful properties or not.
2002 E. Borovitskaya & M. S. Shur Quantum Dots (2003) 7 This evolution from a three dimensional crystal to a quantum well and to a quantum wire has dramatic consequences for the energy spectra.
quantum yield n. = quantum efficiency n.
ΘΚΠ
the world > matter > physics > atomic physics > particle physics > apparatus for detecting charged particles > [noun] > effective proportion of photons
quantum efficiency1926
quantum yield1927
1927 Jrnl. Amer. Chem. Soc. 49 2451 These new facts make possible a better conception of the mechanism of the photochemical decomposition of ammonia... Warburg measured the quantum yield and found it to be 4 quanta per molecule for light of wave length 2025–2140 Å.
1990 EMBO Jrnl. 9 4105/1 Titration with NBD–actin gives a more sensitive assay of binding affinity, provided that interaction affects the quantum yield of the fluorophore.
C3. attributive. Designating a substantial and sudden change, esp. an increase or improvement. Cf. quantum jump n. 2, quantum leap n. 2.
ΚΠ
1931 Times 30 Jan. 10/3 Complete results of the year's trading..will show, without exception, a quantum increase on 1929.
1955 Charleston (Virginia) Gaz. 2 Nov. 9/2 The Navy's planned introduction of a quantum improvement in her armaments.
1974 Sci. Amer. June 105/3 The Upper Paleolithic represents a quantum advance in human cultural evolution.
1991 Forbes 2 Sept. 49/2 We needed a quantum step.
2006 Brantford (Ont.) Expositor (Nexis) 30 Dec. c7 The First World War marked a quantum shift of power to the United States.
This entry has been updated (OED Third Edition, December 2007; most recently modified version published online December 2022).
<
n.adj.1567