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1

Feist, Armin, Guanhao Huang, Germaine Arend, Yujia Yang, Jan-Wilke Henke, Arslan Sajid Raja, F. Jasmin Kappert et al. « Cavity-mediated electron-photon pairs ». Science 377, no 6607 (12 août 2022) : 777–80. http://dx.doi.org/10.1126/science.abo5037.

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Quantum information, communication, and sensing rely on the generation and control of quantum correlations in complementary degrees of freedom. Free electrons coupled to photonics promise novel hybrid quantum technologies, although single-particle correlations and entanglement have yet to be shown. In this work, we demonstrate the preparation of electron-photon pair states using the phase-matched interaction of free electrons with the evanescent vacuum field of a photonic chip–based optical microresonator. Spontaneous inelastic scattering produces intracavity photons coincident with energy-shifted electrons, which we employ for noise-suppressed optical mode imaging. This parametric pair-state preparation will underpin the future development of free-electron quantum optics, providing a route to quantum-enhanced imaging, electron-photon entanglement, and heralded single-electron and Fock-state photon sources.
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2

Edwards, Peter P. « Trapped electron pairs ». Nature 331, no 6157 (février 1988) : 564–65. http://dx.doi.org/10.1038/331564a0.

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3

Kutzelnigg, Werner, et Stefan Vogtner. « Extremal electron pairs ». International Journal of Quantum Chemistry 60, no 1 (5 octobre 1996) : 235–48. http://dx.doi.org/10.1002/(sici)1097-461x(1996)60:1<235 ::aid-qua25>3.0.co;2-c.

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4

Franz, M. « PHYSICS : Crystalline Electron Pairs ». Science 305, no 5689 (3 septembre 2004) : 1410–11. http://dx.doi.org/10.1126/science.1099569.

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5

Peterson, Ivars. « Electron Pairs and Waves ». Science News 149, no 10 (9 mars 1996) : 156. http://dx.doi.org/10.2307/3979661.

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6

Andreev, A. F. « Electron pairs for HTSC ». Journal of Experimental and Theoretical Physics Letters 79, no 2 (janvier 2004) : 88–90. http://dx.doi.org/10.1134/1.1690358.

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7

Singh, R. J., et Shakeel Khan. « Model of electron pairs in electron-doped cuprates ». International Journal of Modern Physics B 30, no 24 (26 septembre 2016) : 1650170. http://dx.doi.org/10.1142/s0217979216501708.

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In the order parameter of hole-doped cuprate superconductors in the pseudogap phase, two holes enter the order parameter from opposite sides and pass through various [Formula: see text] cells jumping from one [Formula: see text] to the other under the influence of magnetic field offered by the [Formula: see text] ions in that [Formula: see text] cell and thus forming hole pairs. In the pseudogap phase of electron-doped cuprates, two electrons enter the order parameter at [Formula: see text] sites from opposite ends and pass from one [Formula: see text] site to the diagonally opposite [Formula: see text] site. Following this type of path, they are subjected to high magnetic fields from various [Formula: see text] ions in that cell. They do not travel from one [Formula: see text] site to the other along straight path but by helical path. As they pass through the diagonal, they face high to low to very high magnetic field. Therefore, frequency of helical motion and pitch goes on changing with the magnetic field. Just before reaching the [Formula: see text] ions at the exit points of all the cells, the pitch of the helical motion is enormously decreased and thus charge density at these sites is increased. So the velocity of electrons along the diagonal path is decreased. Consequently, transition temperature of electron-doped cuprates becomes less than that of hole-doped cuprates. Symmetry of the order parameter of the electron-doped cuprates has been found to be of [Formula: see text] type. It has been inferred that internal magnetic field inside the order parameter reconstructs the Fermi surface, which is requisite for superconductivity to take place. Electron pairs formed in the pseudogap phase are the precursors of superconducting order parameter when cooled below [Formula: see text].
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8

BYTAUTAS, LAIMUTIS, et KLAUS RUEDENBERG. « Electron pairs, localized orbitals and electron correlation ». Molecular Physics 100, no 6 (20 mars 2002) : 757–81. http://dx.doi.org/10.1080/00268970110095165.

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9

Peterson, I. « Electron Pairs in Superconducting Rings ». Science News 145, no 14 (2 avril 1994) : 213. http://dx.doi.org/10.2307/3977816.

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10

Davydov, Alexandr S., et Ivan I. Ukrainskii. « Electron states and electron transport in quasi-one-dimensional molecular systems ». Canadian Journal of Chemistry 63, no 7 (1 juillet 1985) : 1899–903. http://dx.doi.org/10.1139/v85-314.

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It is shown that the concept of electron pairs may be introduced in conducting quasi-one-dimensional systems with electron delocalization such as (CH)x and the stacks of molecule-donors and acceptors of electrons TMTSF, TTT, TCNQ, etc. The introduction of pairing proves to be useful and electronic structure and electronic processes can be easily visualized. The two causative factors in the appearance of pairs in a many-electron system with repulsion are pointed out. The first one is the electron Fermi-statistics that does not allow a spatial region to be occupied by more than two electrons. The second one is the interaction of electrons with a soft lattice. The first of these factors is important at large and intermediate electron densities ρ ≥ 1, the second one dominates at [Formula: see text]. The kink-type excitation parameters in (CH)x are considered with a non-linear potential obtained in an electron-pair approach for the many-electron wave function of (CH)x.
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11

Grigorenko, Ilya, et Roman Ya. Kezerashvili. « Superfluidity of electron–hole pairs between two critical temperatures ». International Journal of Modern Physics B 29, no 27 (27 octobre 2015) : 1550188. http://dx.doi.org/10.1142/s021797921550188x.

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We study a system of spatially separated electrons and holes, assuming the carriers are confined to two parallel planes. The existence of the superfluid state of electron–hole pairs between two critical temperatures is predicted for such system in a case of electron–hole asymmetry caused by the difference in the carrier masses and their chemical potentials. The stability of the superfluid state is studied with respect to the changes of the asymmetry between electrons and holes. It is found that one type of the asymmetry can compensate another one, so the superfluid state is possible in a wide range of the asymmetry parameters when they satisfy a simple linear equation.
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12

Karnaukhov, Igor N. « New Exactly Solvable One-Parameter Model of Strongly Correlated Electrons ». International Journal of Modern Physics B 11, no 30 (10 décembre 1997) : 3543–50. http://dx.doi.org/10.1142/s0217979297001775.

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We present a two band fermion model consisting of a subband of conduction electrons and a subband of local electron pairs interacting via interband interactions. The model is solved in one dimension by means of the Bethe ansatz for an empty subband of local electron pairs. The ground state energy, the chemical potential, the critical exponents, describing the asymptotic behavior of correlation functions at long distances, the effective electron transport mass have been calculated numerically for an arbitrary density of conduction electrons.
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13

HOLLETT, JOSHUA W., et RAYMOND A. POIRIER. « AN INTERESTING RELATIONSHIP BETWEEN INTERELECTRONIC DISTANCE AND THE CORRESPONDING COULOMB INTEGRAL ». Journal of Theoretical and Computational Chemistry 06, no 01 (mars 2007) : 13–22. http://dx.doi.org/10.1142/s0219633607002782.

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A simple expression for the distance between two electrons, (δr12)ab, has been defined from one-electron expectation values. This value is calculated for triplet and singlet systems of two electrons, and closed-shell molecules of up to 58 electrons. When (δr12)ab is compared to the corresponding coulomb integral, Jab, an interesting relationship is observed. The relationship is followed extremely closely by all pairs of electrons, except for some deviations involving delocalized core–core electron pairs.
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14

Munárriz, Julen, Miguel Gallegos, Julia Contreras-García et Ángel Martín Pendás. « Energetics of Electron Pairs in Electrophilic Aromatic Substitutions ». Molecules 26, no 2 (19 janvier 2021) : 513. http://dx.doi.org/10.3390/molecules26020513.

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The interacting quantum atoms approach (IQA) as applied to the electron-pair exhaustive partition of real space induced by the electron localization function (ELF) is used to examine candidate energetic descriptors to rationalize substituent effects in simple electrophilic aromatic substitutions. It is first shown that inductive and mesomeric effects can be recognized from the decay mode of the aromatic valence bond basin populations with the distance to the substituent, and that the fluctuation of the population of adjacent bonds holds also regioselectivity information. With this, the kinetic energy of the electrons in these aromatic basins, as well as their mutual exchange-correlation energies are proposed as suitable energetic indices containing relevant information about substituent effects. We suggest that these descriptors could be used to build future reactive force fields.
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15

Nagaraja, S., L. R. C. Fonseca et J. P. Leburton. « Electron-electron interactions between orbital pairs in quantum dots ». Physical Review B 59, no 23 (15 juin 1999) : 14880–83. http://dx.doi.org/10.1103/physrevb.59.14880.

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16

Massari, Marta, Callum R. Nicoll et Andrea Mattevi. « A lonely electron blocks incoming pairs ». Journal of Biological Chemistry 296 (janvier 2021) : 100294. http://dx.doi.org/10.1016/j.jbc.2021.100294.

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17

Гутій, А. І., et М. Т. Саболчі. « Pacularities of electron-positron pairs production ». Scientific Herald of Uzhhorod University.Series Physics 3 (31 décembre 1998) : 11–12. http://dx.doi.org/10.24144/2415-8038.1998.3.11-12.

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18

Hasegawa, Yuya, Koh Saitoh, Nobuo Tanaka et Masaya Uchida. « Propagation Dynamics of Electron Vortex Pairs ». Journal of the Physical Society of Japan 82, no 7 (15 juillet 2013) : 073402. http://dx.doi.org/10.7566/jpsj.82.073402.

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19

Berakdar, J., H. Klar, A. Huetz et P. Selles. « Chiral electron pairs from double photoionization ». Journal of Physics B : Atomic, Molecular and Optical Physics 26, no 8 (28 avril 1993) : 1463–78. http://dx.doi.org/10.1088/0953-4075/26/8/013.

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20

Ubbelohde, Niels, Frank Hohls, Vyacheslavs Kashcheyevs, Timo Wagner, Lukas Fricke, Bernd Kästner, Klaus Pierz, Hans W. Schumacher et Rolf J. Haug. « Partitioning of on-demand electron pairs ». Nature Nanotechnology 10, no 1 (1 décembre 2014) : 46–49. http://dx.doi.org/10.1038/nnano.2014.275.

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21

Jauregui, Luis A., et Philip Kim. « Curved paths of electron–hole pairs ». Nature Materials 16, no 12 (décembre 2017) : 1169–70. http://dx.doi.org/10.1038/nmat5046.

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22

Sagar, Robin P., Humberto G. Laguna et Nicolais L. Guevara. « Statistical correlation between atomic electron pairs ». Chemical Physics Letters 514, no 4-6 (octobre 2011) : 352–56. http://dx.doi.org/10.1016/j.cplett.2011.08.032.

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23

Narayanan S J, Jishnu, Arnab Bachhar, Divya Tripathi et Achintya Kumar Dutta. « Electron Attachment to Wobble Base Pairs ». Journal of Physical Chemistry A 127, no 2 (9 janvier 2023) : 457–67. http://dx.doi.org/10.1021/acs.jpca.2c07469.

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24

Zhong, Cheng, Jinwei Zhou et Charles L. Braun. « Electron-transfer absorption of sterically bulky donor–acceptor pairs : electron donor–acceptor complexes or random pairs ? » Journal of Photochemistry and Photobiology A : Chemistry 161, no 1 (novembre 2003) : 1–9. http://dx.doi.org/10.1016/s1010-6030(03)00233-8.

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25

Chern, Chyh-Hong. « Theory of superconductivity in strongly correlated electron systems ». International Journal of Modern Physics B 32, no 23 (29 août 2018) : 1850257. http://dx.doi.org/10.1142/s0217979218502570.

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In the correlated electron system with the pseudogap, full-gapped domains and Fermi-arced domains coexist. These domains are created by the quantum-fluctuated antiferromagnetic correlation that generates the short-ranged attractive potential to produce the Fermi arcs and the superconductivity. In the full-gapped domains, s-wave or [Formula: see text]-wave symmetry of the electron pairs is favored. In the Fermi-arced domains, only [Formula: see text]-wave symmetry of pairs is stable. Superconductivity of different pairing symmetry coexists in different domains as well. Different from the Cooper pairs, the correlated electrons pair up in the real space with an energy gap. Gapless states, on the contrary, hinder the development of superconductivity.
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26

GIACOSA, FRANCESCO, et RALF HOFMANN. « BURSTS OF LOW-ENERGY ELECTRON–POSITRON PAIRS IN TeV-RANGE COLLIDER PHYSICS ». Modern Physics Letters A 24, no 24 (10 août 2009) : 1937–42. http://dx.doi.org/10.1142/s0217732309031259.

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In this letter we investigate the possible emission of low-energy electron neutrinos and electron–positron pairs of anomalously large multiplicity in close-to-central pp collisions at LHC. The scenario is based on confining SU(2) Yang–Mills dynamics of Hagedorn temperature ~ me = 511 keV being responsible for the emergence of the lightest lepton family and the weak interactions of the Standard Model. Although cut off by LHC's detectors these electron–positron bursts would be seen indirectly by a large defect energy and thus an anomalously strong decrease of events with interesting high-energy secondaries for increasing [Formula: see text]. This is because the formation of superconducting (preconfining) SU(2) hot-spots "steals" a large fraction of [Formula: see text] subsequently transferring it to a thermal spectrum of electron neutrinos, electrons, and positrons liberated through evaporation. We thus propose the detection of electrons and positrons of kinetic energy ~ me and photons of energy ~ 2me.
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27

POY, Cecília Dominical, et Marinônio Lopes CORNÉLIO. « Electron migration in DNA matrix : an electron transfer reaction ». Eclética Química 23 (1998) : 99–109. http://dx.doi.org/10.1590/s0100-46701998000100009.

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This paper brings an active and provocative area of current research. It describes the investigation of electron transfer (ET) chemistry in general and ET reactions results in DNA in particular. Two DNA intercalating molecules were used: Ethidium Bromide as the donor (D) and Methyl-Viologen as the acceptor (A), the former intercalated between DNA bases and the latter in its surface. Using the Perrin model and fluorescence quenching measurements the distance of electron migration, herein considered to be the linear spacing between donor and acceptor molecule along the DNA molecule, was obtained. A value of 22.6 (± 1.1) angstroms for the distance and a number of 6.6 base pairs between donor and acceptor were found. In current literature the values found were 26 angstroms and almost 8 base pairs. DNA electron transfer is considered to be mediated by through-space interactions between the p-electron-containing base pairs.
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28

Poy, Cecília Dominical, et Marinônio Lopes Cornélio. « Electron migration in DNA matrix : an electron transfer reaction ». Ecletica Quimica 23, no 1 (7 décembre 1998) : 99–109. http://dx.doi.org/10.26850/1678-4618eqj.v23.1.1998.p99-109.

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This paper brings an active and provocative area of current research. It describes the investigation of electron transfer (ET) chemistry in general and ET reactions results in DNA in particular. Two DNA intercalating molecules were used: Ethidium Bromide as the donor (D) and Methyl-Viologen as the acceptor (A), the former intercalated between DNA bases and the latter in its surface. Using the Perrin model and fluorescence quenching measurements the distance of electron migration, herein considered to be the linear spacing between donor and acceptor molecule along the DNA molecule, was obtained. A value of 22.6 (± 1.1) angstroms for the distance and a number of 6.6 base pairs between donor and acceptor were found. In current literature the values found were 26 angstroms and almost 8 base pairs. DNA electron transfer is considered to be mediated by through-space interactions between the p-electron-containing base pairs.
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29

Proud, Adam Jonathan, Brendan James Henry Sheppard et Jason Kenneth Pearson. « Revealing Electron–Electron Interactions within Lewis Pairs in Chemical Systems ». Journal of the American Chemical Society 140, no 1 (20 décembre 2017) : 219–28. http://dx.doi.org/10.1021/jacs.7b08935.

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30

Treumann, Rudolf A., et Wolfgang Baumjohann. « Electron pairing in mirror modes : surpassing the quasi-linear limit ». Annales Geophysicae 37, no 5 (24 octobre 2019) : 971–88. http://dx.doi.org/10.5194/angeo-37-971-2019.

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Abstract. The mirror mode evolving in collisionless magnetised high-temperature thermally anisotropic plasmas is shown to develop an interesting macro-state. Starting as a classical zero-frequency ion fluid instability it saturates quasi-linearly at very low magnetic level, while forming elongated magnetic bubbles which trap the electron component to perform an adiabatic bounce motion along the magnetic field. Further evolution of the mirror mode towards a stationary state is determined by the bouncing trapped electrons which interact with the thermal level of ion sound waves and generate attractive wake potentials which give rise to the formation of electron pairs in the lowest-energy singlet state of two combined electrons. Pairing preferentially takes place near the bounce-mirror points where the pairs become spatially locked with all their energy in the gyration. The resulting large anisotropy of pairs enters the mirror growth rate in the quasi-linearly stable mirror mode. It breaks the quasi-linear stability and causes further growth. Pressure balance is either restored by dissipation of the pairs and their anisotropy or inflow of plasma from the environment. In the first case new pairs will continuously form until equilibrium is reached. In the final state the fraction of pairs can be estimated. This process is open to experimental verification. To our knowledge it is the only process in which high-temperature plasma pairing may occur and has an important observable macroscopic effect: breaking the quasi-linear limit and, via pressure balance, generation of localised diamagnetism.
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31

Mauksch, Michael, et Svetlana B. Tsogoeva. « Spin-paired solvated electron couples in alkali–ammonia systems ». Physical Chemistry Chemical Physics 20, no 44 (2018) : 27740–44. http://dx.doi.org/10.1039/c8cp05058a.

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32

Ponec, Robert, et Filip Uhlík. « Electron Pairing and Chemical Bonds. Physical Meaning of Effective Pairs ». Collection of Czechoslovak Chemical Communications 59, no 12 (1994) : 2567–78. http://dx.doi.org/10.1135/cccc19942567.

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The physical meaning of the so-called effective pairs which have been introduced recently within the formalism of pair population analysis is discussed using the analysis of conditional probabilities of electron density distribution for electron 1 with the reference electron fixed in a certain point 2. It is demonstrated that from the point of view of the mutual coupling of electron motions, the effective pairs behave analogously to singlet pairs. Based on this finding, effective pairs can be interpreted as the fraction of singlet pairs that is directly involved in bonding.
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33

Liang, W. Y. « A Model for Correlated Valence Fluctuation in High Tc Superconductors ». International Journal of Modern Physics B 01, no 03n04 (août 1987) : 1049–55. http://dx.doi.org/10.1142/s0217979287001547.

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A simple model is proposed as a possible mechanism for high T c superconductivity in certain copper oxides based on correlated valence fluctuation. Electron pairs are formed by Coulomb attraction between electrons in mainly Cu2+ ( d 9 configuration) pyramidal planes mediated by Cu 3+ ( d 8 configuration) ions in the CuO 4 chain-like plane in YBa2Cu3O7−x . These electron pairs have high binding energies necessary for high Tc , and the model is capable of explaining a number of other observed properties.
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34

van der Put, P. J. « Electron pairs shed light on frustrated percolation ». Nature 392, no 6671 (mars 1998) : 29–30. http://dx.doi.org/10.1038/32071.

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35

Bockman, T. M., et Jay K. Kochi. « Photoinduced electron transfer in contact ion pairs ». Journal of the American Chemical Society 110, no 4 (février 1988) : 1294–95. http://dx.doi.org/10.1021/ja00212a049.

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36

Ramírez, Carlos, et Chumin Wang. « Bose–Einstein Condensation of Collective Electron Pairs ». Journal of Low Temperature Physics 175, no 1-2 (15 décembre 2013) : 295–304. http://dx.doi.org/10.1007/s10909-013-0998-z.

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37

White, Timothy R., et Alan P. Lightman. « Hot accretion disks with electron-positron pairs ». Astrophysical Journal 340 (mai 1989) : 1024. http://dx.doi.org/10.1086/167455.

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38

Šmit, Ž. « Double photoionization ofK- andL-shell electron pairs ». Physical Review A 40, no 11 (1 décembre 1989) : 6303–7. http://dx.doi.org/10.1103/physreva.40.6303.

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39

Kempf, J., M. Nonnenmacher et H. H. Wagner. « Photoexcitation of electron-hole pairs during SIMS ». Applied Physics A Solids and Surfaces 49, no 3 (septembre 1989) : 279–83. http://dx.doi.org/10.1007/bf00616855.

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40

Lucente, Giuseppe. « Supernova bounds on axion-like particles coupled with nucleons and electrons ». Journal of Physics : Conference Series 2156, no 1 (1 décembre 2021) : 012085. http://dx.doi.org/10.1088/1742-6596/2156/1/012085.

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Abstract We investigate the potential of type II supernovae (SNe) to constrain axion-like particles (ALPs) coupled simultaneously to nucleons and electrons. ALPs coupled to nucleons can be efficiently produced in the SN core via nucleon-nucleon bremsstrahlung and, for masses exceeding 1 MeV, they would decay into electron-positron pairs, generating a positron flux. In the case of Galactic SNe, the annihilation of the created positrons with the electrons in the Galaxy would contribute to the 511 keV annihilation line. The SPI (SPectrometer on INTEGRAL) observation of this line allows us to exclude a wide range of the axion-electron coupling, 10−19 < gae < 10−11, for gap – 10−9. Additionally, ALPs from extra-galactic SNe decaying into electron-positron pairs would yield a contribution to the cosmic X-ray background. In this case, we constrain the ALP-electron coupling down to gae ∼ 10−20.
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41

Bastiaans, Koen M., Damianos Chatzopoulos, Jian-Feng Ge, Doohee Cho, Willem O. Tromp, Jan M. van Ruitenbeek, Mark H. Fischer et al. « Direct evidence for Cooper pairing without a spectral gap in a disordered superconductor above T c ». Science 374, no 6567 (29 octobre 2021) : 608–11. http://dx.doi.org/10.1126/science.abe3987.

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Measuring the effective charge At low enough temperatures, superconductors are capable of conducting electricity without any resistance because of the formation of so-called Cooper pairs of electrons. Cooper pairs typically form at the same critical temperature at which superconductivity sets in. In certain materials, they are thought to form above that temperature, but showing this property directly in an experiment is tricky. Bastiaans et al . used tunneling noise spectroscopy to measure the effective charge of current carriers in the disordered superconductor titanium nitride. As expected, below the critical temperature, the effective charge was equal to two electron charges. However, this behavior persisted above the critical temperature, indicating that electron pairs exist in that regime. —JS
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42

Jeschke, Gunnar. « Electron–electron–nuclear three-spin mixing in spin-correlated radical pairs ». Journal of Chemical Physics 106, no 24 (22 juin 1997) : 10072–86. http://dx.doi.org/10.1063/1.474063.

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43

Shin, Mincheol, Seongjae Lee, Kyoung Wan Park et Gwang-Hee Kim. « Coulomb blockade by electron-hole pairs in coupled single-electron transistors ». Physical Review B 62, no 15 (15 octobre 2000) : 9951–54. http://dx.doi.org/10.1103/physrevb.62.9951.

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44

Lv, Hua, Jing Guang, Yumin Liu, Haibo Tang, Peng Zhang, Yan Lu et Jianji Wang. « Synthesis of ionic liquid-modified BiPO4 microspheres with hierarchical flower-like architectures and enhanced photocatalytic activity ». RSC Advances 5, no 122 (2015) : 100625–32. http://dx.doi.org/10.1039/c5ra14626g.

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45

Annadi, Anil, Guanglei Cheng, Hyungwoo Lee, Jung-Woo Lee, Shicheng Lu, Anthony Tylan-Tyler, Megan Briggeman et al. « Quantized Ballistic Transport of Electrons and Electron Pairs in LaAlO3/SrTiO3 Nanowires ». Nano Letters 18, no 7 (20 juin 2018) : 4473–81. http://dx.doi.org/10.1021/acs.nanolett.8b01614.

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46

LOTZE, K. H. « SIMULTANEOUS CREATION OF ELECTRON–POSITRON PAIRS AND PHOTONS IN ROBERTSON–WALKER UNIVERSES WITH STATICALLY BOUNDED EXPANSION ». International Journal of Modern Physics A 07, no 12 (10 mai 1992) : 2695–712. http://dx.doi.org/10.1142/s0217751x92001216.

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We present, based upon quantum electrodynamics in Robertson–Walker flat universes, a thorough analysis of the creation of mutually interacting electron–positron pairs and photons from vacuum. Therefore we discuss at least qualitatively all processes contributing to the number densities of created particles up to the second order in the coupling constant. For two particular expansion laws with Minkowskian in respectively in and out regions, we obtain exact solutions to the Dirac equation and investigate in detail the process of simultaneous creation of electron–positron pairs and photons and the related attenuation effect for fermionic particles. This is done for electrons and positrons which have nonrelativistic momenta at Compton time in rapidly expanding universes. The results are compared with the zeroth-order creation of electron–positron pairs. Despite being smaller by a factor of roughly [Formula: see text], the interacting-particle creation is important mainly as a source of photons even in conformally flat universes.
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47

Iglev, Hristo, Martin K. Fischer et Alfred Laubereau. « Electron detachment from anions in aqueous solutions studied by two- and three-pulse femtosecond spectroscopy ». Pure and Applied Chemistry 82, no 10 (30 juin 2010) : 1919–26. http://dx.doi.org/10.1351/pac-con-09-12-04.

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The electron photodetachment of the aqueous halides and hydroxide is studied after resonant excitation in the lowest charge-transfer-to-solvent (CTTS) state. The initially excited state is followed by an intermediate assigned to a donor-electron pair that displays a competition of recombination and separation. Using pump–repump–probe (PREP) spectroscopy, the pair species is verified via a secondary excitation with separation of the pairs so that the yield of released electrons is increased. The observed recombination process on the one hand and the similar absorptions of the intermediate and the hydrated electron on the other hand suggest that the donor-electron pairs incorporate only few if not just one water molecule. The geminate dynamics measured in the various CTTS systems reveal a strong influence of the parent radical. The electron survival probability decreases significantly from 0.77 to 0.29 going from F– to OH–. The extracted dissociation rates of the halogen-electron pairs seem to be proportional to the mutual diffusion coefficients of the geminate particles, while such a relation between the recombination rate and the diffusion coefficient is not found. Results for I– show that excitation of a higher-lying CTTS state opens a new relaxation channel, which directly leads to a fully hydrated electron, while the relaxation channel discussed above is not significantly affected.
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Tengowski, Mark W. « Converting Right-Left Stereo Pairs into Colored Pairs for Electronic Presentation ». Microscopy Today 11, no 6 (décembre 2003) : 52. http://dx.doi.org/10.1017/s1551929500053487.

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Since Microsoft PowerPoint has become the dominant scientific meeting presentation format, my collection of right-left stereo slide pairs has basically been rendered obsolete. Yet, contained within these striking images are valuable scientific data. This communication describes an easy method whereby analog slide data (i.e. scanning electron micrograph RL pairs, Figs. 1 & 2) are transformed into an electronic format such that the need for projector polarizers is replaced by inexpensive red-green or red-blue 3-D glasses.
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Conti, Sara, Andrea Perali, François M. Peeters et David Neilson. « Effect of Mismatched Electron-Hole Effective Masses on Superfluidity in Double Layer Solid-State Systems ». Condensed Matter 6, no 2 (7 avril 2021) : 14. http://dx.doi.org/10.3390/condmat6020014.

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Superfluidity has been predicted and now observed in a number of different electron-hole double-layer semiconductor heterostructures. In some of the heterostructures, such as GaAs and Ge-Si electron-hole double quantum wells, there is a strong mismatch between the electron and hole effective masses. We systematically investigate the sensitivity to unequal masses of the superfluid properties and the self-consistent screening of the electron-hole pairing interaction. We find that the superfluid properties are insensitive to mass imbalance in the low density BEC regime of strongly-coupled boson-like electron-hole pairs. At higher densities, in the BEC-BCS crossover regime of fermionic pairs, we find that mass imbalance between electrons and holes weakens the superfluidity and expands the density range for the BEC-BCS crossover regime. This permits screening to kill the superfluid at a lower density than for equal masses.
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Keszei, Ernö, et Jean-Paul Jay-Gerin. « On the role of the parent cation in the dynamics of formation of laser-induced hydrated electrons ». Canadian Journal of Chemistry 70, no 1 (1 janvier 1992) : 21–23. http://dx.doi.org/10.1139/v92-004.

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A short account is given of the continuum and molecular descriptions of the formation of hydrated electrons. Starting with a scheme of hydration dynamics of laser-induced electrons that accounts for the formation of hydrated electrons without invoking the "direct" ionization of water, a new model explaining the dynamics of electron hydration in terms of a molecular description is proposed. According to this model, the parent cation plays an active role in the trapping of electrons, deepening electron traps that preexist in the liquid before excitation. Consequences of this description to the transient absorption spectra are briefly discussed. Keywords: laser-induced electron – cation pairs, hydrated electron formation, liquid water.
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