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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : PARLINSKI K., CURRAT R., VETTIER C., ALEKSANDROVA I. P., ECKOLD G.
Заглавие : Effect of hydrostatic-pressure on modulated phases in Rb2ZnBr4
Разночтения заглавия :авие SCOPUS: Effect of hydrostatic pressure on modulated phases in Rb2ZnBr4
Место публикации : Phys. Rev. B. - 1992. - Vol. 46, Is. 1. - P.106-114. - ISSN 0163-1829, DOI 10.1103/PhysRevB.46.106
Примечания : Cited References: 36
Предметные рубрики: INCOMMENSURATE PHASES
NEUTRON-SCATTERING
X-RAY
COMMENSURATE
TRANSITIONS
EVOLUTION
MODEL
WAVE
Аннотация: Neutron-diffraction studies on modulated Rb2ZnBr4, carried out under hydrostatic pressure, revealed two new commensurate phases characterized by wave vectors q = 2/7b* and q = 1/4b*, respectively. The first order phase transition between them is revealed by the coexistence of two distinct peaks in the diffraction pattern. The observed pressure-temperature phase diagram contains: the above-mentioned phases, the ferroelectric commensurate phase q = 1/3, and a region characterized by wave-vector values in the interval q = 2/7-1/3. In this region the modulation wave vector exhibits stepwise behavior as a function of pressure, but remains nearly constant iii temperature runs. We have found in this region a characteristic memory effect in which two temperature runs performed at the same pressure lead to two different modulation wave-vector values, while only the thermal history of the sample is different in the two runs. At ambient pressure we confirm the presence of a multipeaked diffraction pattern just above the lock-in transition to the commensurate q = 1/3 phase. At 122 K the phase transition from the 1/3 phase to the 1/4 phase is detected in pressure scans. The transition mechanism involves the q = 2/7 phase, at least as a metastable intermediate phase.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : OVCHINNIKOV S. G.
Заглавие : DENSITY OF SINGLE-PARTICLE STATES IN STRONGLY CORRELATED ELECTRON-SYSTEMS IN COPPER OXIDES
Место публикации : Zhurnal Eksperimentalnoi Teor. Fiz.: MEZHDUNARODNAYA KNIGA, 1993. - Vol. 104, Is. 5. - P3719-3734. - ISSN 0044-4510
Примечания : Cited References: 24
Предметные рубрики: DYNAMIC PROPERTIES
BAND
SPECTRA
MODEL
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G.
Заглавие : Density of hole-doped states in strongly correlated electron-systems of copper oxides
Разночтения заглавия :авие SCOPUS: Density of hole-doped states in strongly correlated electron systems of copper oxides
Место публикации : Phys. Rev. B. - 1994. - Vol. 49, Is. 14. - P.9891-9897. - ISSN 0163-1829, DOI 10.1103/PhysRevB.49.9891
Примечания : Cited References: 34
Предметные рубрики: DYNAMIC PROPERTIES
SUPERCONDUCTIVITY
GAP
LA2CUO4
BI2SR2CACU2O8
PHOTOEMISSION
SPECTROSCOPY
SPECTRA
MODEL
BAND
Аннотация: A generalized tight-binding method to calculate quasiparticle band structure and density of states in strongly correlated systems is presented. The band structures of undoped and weakly hole-doped CuO2 layer are calculated. The insulator gap has a charge transfer nature with a minor contribution from a Cu-O Coulomb interaction. Doping results in the appearance of an in-gap state with a simultaneous decrease of the density of states at the band edges in agreement with small cluster results and experimental data.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Deich L. I.
Заглавие : Far-infrared attenuation in glasses
Разночтения заглавия :авие SCOPUS: Far-infrared attenuation in glasses
Место публикации : Phys. Rev. B. - 1994. - Vol. 49, Is. 1. - P.109-113. - ISSN 0163-1829, DOI 10.1103/PhysRevB.49.109
Примечания : Cited References: 29
Предметные рубрики: VITREOUS SILICA
TEMPERATURE
MODEL
LOCALIZATION
ABSORPTION
SOLIDS
STATES
Аннотация: The influence of quasilocal vibrations on the far-infrared spectra of glasses is investigated under the supposition that the quasilocal vibrations are directly inactive in the attenuation. It is shown that taking into account phonon-quasilocal-vibration coupling and both medium- and short-range structure of the inhomogeneities of a photon-phonon coupling parameter can give rise to an attenuation curve similar to one observed for a-SiO2 and related materials.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : OVCHINNIKOV S.G.
Заглавие : THE INFLUENCE OF THE ANTIFERROMAGNETISM ON THE ELECTRONIC-STRUCTURE OF LA2CUO4
Разночтения заглавия :авие SCOPUS: The influence of the antiferromagnetism on the electronic structure of La2CuO4
Место публикации : J. Supercond.: PLENUM PUBL CORP, 1995. - Vol. 8: University-of-Miami Workshop on High-Temperature Superconductivity - Physical Properties and Mechanisms (JAN 05-11, 1995, CORAL GABLES, FL), Is. 5. - P675-676. - ISSN 0896-1107, DOI 10.1007/BF00727473
Примечания : Cited References: 15
Предметные рубрики: OXIDES
MODEL
Ключевые слова (''Своб.индексиров.''): electron correlations--electron structure--spin fluctuations--electron correlations--electron structure--spin fluctuations--antiferromagnetism--band structure--calculations--correlation theory--electrons--lanthanum compounds--paramagnetism--perturbation techniques--antiferromagnetic phase--electron correlations--intercluster interactions--spin fluctuations--electronic structure
Аннотация: The quasiparticle approach for electronic structure calculations considering strong electron correlations is given. The exact diagonalization of a multiband Hubbard Hamiltonian for a small cluster is combined with perturbation theory for intercluster hopping. The band structure of paramagnetic and antiferromagnetic La2CuO4 are discussed.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G.
Заглавие : EFFECT OF ANTIFERROMAGNETIC ORDERING ON ZONE STRUCTURE OF LA2CUO4
Место публикации : Zhurnal Eksperimentalnoi Teor. Fiz.: MEZHDUNARODNAYA KNIGA, 1995. - Vol. 107, Is. 3. - P796-811. - ISSN 0044-4510
Примечания : Cited References: 42
Предметные рубрики: HIGH-TC SUPERCONDUCTORS
ELECTRONIC-STRUCTURE
OXIDE SUPERCONDUCTORS
CHARGE-TRANSFER
CUO2 PLANE
MODEL
HOLE
SPECTRUM
STATE
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : SANDALOV I. S., HJORTSTAM O., JOHANSSON B., ERIKSSON O.
Заглавие : ORBITAL POLARIZATION IN METALLIC F-ELECTRON SYSTEMS
Разночтения заглавия :авие SCOPUS: Orbital polarization in metallic f-electron systems
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 1995. - Vol. 51, Is. 20. - P13987-14000. - ISSN 0163-1829, DOI 10.1103/PhysRevB.51.13987
Примечания : Cited References: 28
Предметные рубрики: MOTT INSULATORS
VOLUME COLLAPSE
CERIUM
LOCALIZATION
TRANSITION
PHASES
MODEL
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S.
Заглавие : Dimerization of antiferromagnetic chain with 4-spin interaction
Место публикации : Fiz. Tverd. Tela: MEZHDUNARODNAYA KNIGA, 1996. - Vol. 38, Is. 6. - P1868-1877. - ISSN 0367-3294
Примечания : Cited References: 30
Предметные рубрики: SPIN-1/2 HEISENBERG-ANTIFERROMAGNET
COMPETING INTERACTIONS
MONTE-CARLO
THERMODYNAMIC PROPERTIES
SYSTEMS
CUGEO3
TEMPERATURE
NEUTRON
STATE
MODEL
WOS
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bulgakov E. N., Sadreev A. F.
Заглавие : Current-voltage characteristics of the resonant tunnelling double-barrier structure under time-periodical perturbation
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 1996. - Vol. 8, Is. 45. - P.8869-8887. - ISSN 0953-8984, DOI 10.1088/0953-8984/8/45/020
Примечания : Cited References: 38
Предметные рубрики: SEMICONDUCTOR DOUBLE-BARRIER
OSCILLATING QUANTUM-WELL
DEPENDENT TRANSPORT
INFRARED-RADIATION
TUNNELING TIMES
HETEROSTRUCTURES
TRANSMISSION
MODEL
FREQUENCIES
COHERENT
Аннотация: We consider a typical semiconductor resonant tunnelling GaAs/AlGaAs/GaAs nanostructure which forms a double-barrier potential with quasienergy levels corresponding to transition frequencies in the infrared and microwave regions. Two types of dynamical perturbation of the heterostructure in the form V-1(x, t) = V(1)x cos Omega t and V-2(t) = V-2 cos Omega t are considered. We analyse numerically a reconstruction of the electron transmission through the heterostructure and the current-voltage characteristics (IVC) under the influence of these dynamical perturbations. Both weak and strong perturbations are considered. We investigate the dependences of the transmission on the electron energy and the frequency of the external field with the main accent on the case where a frequency of the perturbation is tuned to a transition between quasienergies of the double-barrier structure. it is found that these resonant phenomena give rise to new peaks and dips in the IVC. In particular, it is shown that the dipole type of perturbation V-1(x, t) gives rise to a Rabi splitting of the transmission peaks and under certain conditions to a Rabi splining of the IVC peaks and dips. We demonstrate that dynamical perturbation may induce a direct current opposite to the direction of the applied voltage, and that this phenomenon takes the form of a sharp dip which has a resonant origin. It is observed that the dipole type of perturbation V-1(x, t) of laser radiation is more effective for tuning the IVC than the first perturbation V-2(t). Also absorption and emission of energy by an electron transmitted through the DBRTS are considered.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sadreev A. F., Sukhinin Y. V.
Заглавие : Phase transitions in a system of CH3(CH2)(n-1) self-assembled on the Au(111) crystal surface
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 1996. - Vol. 54, Is. 24. - P17966-17973. - ISSN 1098-0121, DOI 10.1103/PhysRevB.54.17966
Примечания : Cited References: 44
Предметные рубрики: ORGANIZED MOLECULAR ASSEMBLIES
ALKYL THIOL MONOLAYERS
STRUCTURAL CHARACTERIZATION
DYNAMICS SIMULATION
DEVILS STAIRCASE
GOLD SURFACES
FILMS
MODEL
CHAIN
DIFFRACTION
Аннотация: The n-alkanethiols CH3(CH2)(n-1) on the crystal surface of gold (111) are considered. Couplings between atoms (C, H) of the n-alkanethiols were modelled by the Morse potential, and couplings between the n-alkanethiols and the crystal surface were modelled by 12-3 potentials. Because of symmetry Z(2) of the n-alkanethiols in a tilted state, the system can be reduced to the Ising model on the triangular lattice, the phase diagram of which can be explicitly considered. Depending on the choice of the coupling parameters, the ordered state of the system may form an incommensurate or 2X1 superstructure. The temperatures of the phase transition, equilibrium tilting, twisting, and azimuthal angles are found to depend on the Morse coupling constants.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zobov V. E., Popov M. A.
Заглавие : On the radius of convergence of series in powers of time for spin correlation functions of the Heisenberg magnet at high temperature
Место публикации : Theor. Math. Phys.: PLENUM PUBL CORP, 1997. - Vol. 112, Is. 3. - P1182-1191. - ISSN 0040-5779, DOI 10.1007/BF02583049
Примечания : Cited References: 22
Предметные рубрики: AUTO-CORRELATION FUNCTION
INFINITE-TEMPERATURE
PARAMAGNET
DYNAMICS
MODEL
Аннотация: The convergence of series in powers of time for spin autocorrelation functions of the Heisenberg magnet are investigated at infinite temperatures on lattices of different dimensions d. The calculation data available at the present time for the coefficients of these series are used to estimate the corresponding radii of convergence, whose growth with decreasing d is revealed and explained in a self-consistent approximation. To this end, a simplified nonlinear equation corresponding to this approximation is suggested and solved for the autocorrelation function of a system with an arbitrary number Z of nearest neighbors. The coefficients of the expansion in powers of time for the solution are represented in the form of trees on the Bethe lattice with the coordination number Z. A computer simulation method is applied to calculate the expansion coefficients for trees embedded in square, triangular, and simple cubic lattices under the condition that the intersection of tree branches is forbidden. It is found that the excluded volume effect that manifests itself in a decrease in these coefficients and in an increase in the coordinate and exponent of the singularity of the autocorrelation function on the imaginary time axis is intensified with decreasing lattice dimensions.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sukhinin Y. V.
Заглавие : Phase transitions in self-assembled monolayers of alkanethiols containing the polar group
Место публикации : J. Exp. Theor. Phys.: AMER INST PHYSICS, 1998. - Vol. 87, Is. 1. - P115-122. - ISSN 1063-7761, DOI 10.1134/1.558645
Примечания : Cited References: 38
Предметные рубрики: ORGANIZED MOLECULAR ASSEMBLIES
ALKYL THIOL MONOLAYERS
STRUCTURAL CHARACTERIZATION
DYNAMICS SIMULATION
LANGMUIR MONOLAYER
SURFACES
GOLD
FILMS
AU(111)
MODEL
Аннотация: Equilibrium states of the system of self-assembled monolayers (SAMs) of n-alkanethiol molecules HS(CH2)(n-1)(X) with polar group X chemiabsorbed on the Au(111) crystal surface are considered. The couplings between the atoms (C, H) of the n-alkanethiols are approximated by the Lennard-Jones potential. The couplings between the n-alkanethiols and the crystal surface are approximated by the 12-3 potential. The interactions of polar groups and the self-images with the metal substrate are taken into consideration. The phase-transition temperatures, the structural order and equilibrium tilt, and the twist and azimuthal angles of the macromolecules, which depend on the dipole moments, are found. (C) 1998 American Institute of Physics.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S.
Заглавие : Quantum Monte Carlo analysis of the 2D Heisenberg antiferromagnet with S=1/2: the influence of exchange anisotropy
Разночтения заглавия :авие SCOPUS: Quantum Monte Carlo analysis of the 2D Heisenberg antiferromagnet with S = 1/2: The influence of exchange anisotropy
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 1998. - Vol. 10, Is. 44. - P10061-10065. - ISSN 0953-8984, DOI 10.1088/0953-8984/10/44/012
Примечания : Cited References: 21
Предметные рубрики: SQUARE LATTICE
SYSTEMS
MODEL
Аннотация: The two-dimensional (2D) Heisenberg model with exchange anisotropy Delta = 1 - J(x)/J(z) (J 0) and S
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S.
Заглавие : A study of anisotropic Heisenberg antiferromagnet with S=1/2 on a square lattice by Monte-Carlo method
Место публикации : Phys. Status Solidi B. - 1998. - Vol. 207, Is. 2. - P.491-498. - ISSN 0370-1972, DOI 10.1002/(SICI)1521-3951(199806)207:2491::AID-PSSB4913.0.CO;2-G
Примечания : Cited References: 24
Предметные рубрики: EU2CUO4
LA2CUO4
ORDER
MODEL
STATE
Аннотация: The two-dimensional (2D) Heisenberg model (J 0) with anisotropic exchange Delta = 1-J(X)/J(Z) greater than or equal to 0 and with S = 1/2 is studied by the quantum Monte-Carlo method. Energy, susceptibility, specific heat, spin-spin correlation functions, and correlation radius are calculated. The dependence of the Neel temperature T(N)/J = 2/ln(11/Delta) on the exchange anisotropy is determined. The static magnetic factor is very slowly decreased for T/J 0.4. It is assumed to realize topological excitations in the range of these temperatures. The correlation radius of the isotropic Heisenberg model is fitted by the dependence 1/xi = 2.05T(1.0(6))/exp (1.0(4)/T).The temperature behavior of the static structural magnetic factor in La(2)CuO(4) and Er(2)CuO(4) for T T(N) is in agreement with the MC calculations.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gekht R. S., Bondarenko I. N.
Заглавие : Magnetic ordering and phase transitions in planar antiferromagnetic systems with a Kagome lattice
Место публикации : J. Exp. Theor. Phys.: AMER INST PHYSICS, 1998. - Vol. 86, Is. 6. - P1209-1215. - ISSN 1063-7761, DOI 10.1134/1.558592
Примечания : Cited References: 23
Предметные рубрики: TRIANGULAR LATTICE
2 DIMENSIONS
SPIN
MODEL
Аннотация: We study the process of magnetic ordering in planar antiferromagnetic systems with a Kagome lattice. It is found that if the interaction between next-nearest-neighbor spins is taken into account, the heat capacity of such systems has a singularity at a finite temperature T. On the basis of a scaling analysis of finite-size systems we study the behavior of thermodynamic quantities in the neighborhood of a phase transition. We find that the phase transition at the critical point is due to discrete- and continuous-symmetry breaking, in which the long-range chiral order and the power-law translational spin order emerge simultaneously. Finally, we calculate the temperatures of the transition to different (with three and nine spins per unit cell) ordered states. (C) 1998 American Institute of Physics.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G.
Заглавие : Role of zinc and nickel impurities in high-temperature superconductors
Место публикации : Phys. Solid State: AMER INST PHYSICS, 1999. - Vol. 41, Is. 4. - P534-538. - ISSN 1063-7834, DOI 10.1134/1.1130819
Примечания : Cited References: 32
Предметные рубрики: PR2-XCEXCUO4+DELTA SINGLE-CRYSTALS
SR-CU-O
COPPER OXIDES
MAGNETIC-PROPERTIES
NI
MODEL
ZN
SUBSTITUTION
SCATTERING
SPECTRUM
Аннотация: The local changes produced in the electronic structure and their effect on the physical properties of the superconducting and normal phases when zinc and nickel are substituted for copper are examined on the basis of a multiband p-d model. It is shown that strong electronic correlations suppress the S = 1 configuration of Ni2+ and cause the superposition of the S = 1/2 and S = 0 states of nickel. The change in the density of states in p- and n-type systems is studied, and the peculiarity of Zn impurity for p- type systems and Ni impurity for n-type systems is shown. The universal dependence of the T-c on the residual resistance in lightly doped superconductors and deviations from it in optimally doped systems are discussed. (C) 1999 American Institute of Physics. [S1063-7834(99)00704-2].
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Erkaev N. V., Biernat H. K., Farrugia C. J.
Заглавие : Ideal magnetohydrodynamic flow around a blunt body under anisotropic pressure
Место публикации : Phys. Plasmas: AMER INST PHYSICS, 2000. - Vol. 7, Is. 8. - P3413-3420. - ISSN 1070-664X, DOI 10.1063/1.874205
Примечания : Cited References: 23
Предметные рубрики: MHD FLOW
MAGNETOSHEATH
DEPLETION
CLOSURE
FLUID
MODEL
Аннотация: The plasma flow past a blunt obstacle in an ideal magnetohydrodynamic (MHD) model is studied, taking into account the tensorial nature of the plasma pressure. Three different closure relations are explored and compared with one another. The first one is the adiabatic model proposed by Chew, Goldberger, and Low. The second closure is based on the mirror instability criterion, while the third depends on an empirical closure equation obtained from observations of solar wind flow past the Earth's magnetosphere. The latter is related with the criterion of the anisotropic ion cyclotron instability. In the presented model, the total pressure, defined as the sum of magnetic pressure and perpendicular plasma pressure, is assumed to be a known function of Cartesian coordinates. The calculation is based on the Newtonian approximation for the total pressure along the obstacle and on a quadratic behavior with distance from the obstacle along the normal direction. Profiles of magnetic field strength and plasma parameters are presented along the stagnation stream line between the shock and obstacle of an ideal plasma flow with anisotropy in thermal pressure and temperature. (C) 2000 American Institute of Physics. [S1070- 664X(00)04407-4].
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Erkaev N. V., Semenov V. S., Alexeev I. V., Biernat H. K.
Заглавие : Rate of steady-state reconnection in an incompressible plasma
Место публикации : Phys. Plasmas: AMER INST PHYSICS, 2001. - Vol. 8, Is. 11. - P4800-4809. - ISSN 1070-664X, DOI 10.1063/1.1410112
Примечания : Cited References: 16
Предметные рубрики: MAGNETIC RECONNECTION
CURRENT SHEETS
MODEL
Аннотация: The reconnection rate is obtained for the simplest case of two-dimensional (2D) symmetric reconnection in an incompressible plasma. In the short note [Erkaev , Phys. Rev. Lett. 84, 1455 (2000)], the reconnection rate is found by matching the outer Petschek solution and the inner diffusion region solution. Here the details of the numerical simulation of the diffusion region are presented and the asymptotic procedure which is used for deriving the reconnection rate is described. The reconnection rate is obtained as a decreasing function of the diffusion region length. For a sufficiently large diffusion region scale, the reconnection rate becomes close to that obtained in the Sweet-Parker solution with the inverse square root dependence on the magnetic Reynolds number Re-m, determined for the global size of the current sheet. On the other hand, for a small diffusion region length scale, the reconnection rate turns out to be very similar to that obtained in the Petschek model with a logarithmic dependence on the magnetic Reynolds number Re-m. This means that the Petschek regime seems to be possible only in the case of a strongly localized conductivity corresponding to a small scale of the diffusion region. (C) 2001 American Institute of Physics.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gavrichkov V. A., Borisov A. A., Ovchinnikov S. G.
Заглавие : Polarized ARPES spectra of undoped cuprates
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2001. - Vol. 43, Is. 10. - P1876-1884. - ISSN 1063-7834, DOI 10.1134/1.1410625
Примечания : Cited References: 15
Предметные рубрики: ELECTRONIC-STRUCTURE
COPPER OXIDES
PHOTOEMISSION
EVOLUTION
MODEL
HOLE
Аннотация: The spectral density (SD) in the ARPES spectra of anti ferromagnetic (AFM) dielectrics Sr2CuO2Cl2 and Ca2CuO2Cl2 along the principal symmetry directions of the Brillouin zone was studied by the generalized tight binding method. At the valence band top of these undoped cuprates in the AFM state, there is a pseudogap of magnetic nature with E-s(k) similar to 0-0.4 eV between a virtual level and the valence band proper. The observed similarity of dispersion along the Gamma -M and X-Y directions can be explained by the proximity of the B-3(1g) triplet and the Zhang-Rice singlet levels. The value of parity of the polarized ARPES spectra at the Gamma, M, and X points calculated for the AFM phase of undoped cuprates with an allowance for the partial contributions is even. The conditions favoring observation of the partial contributions in polarized ARPES spectra are indicated. Due to the spin fluctuations, the virtual level acquires dispersion and possesses a small spectral weight. Probably, this level cannot be resolved on the background of the main quasi-particle peak as a result of the damping effects. (C) 2001 MAIK "Nauka/Interperiodica".
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fransson J., Eriksson O., Sandalov I.
Заглавие : Many-body approach to spin-dependent transport in quantum dot systems
Место публикации : Phys. Rev. Lett.: AMERICAN PHYSICAL SOC, 2002. - Vol. 88, Is. 22. - Ст.226601. - ISSN 0031-9007, DOI 10.1103/PhysRevLett.88.226601
Примечания : Cited References: 37
Предметные рубрики: SINGLE-ELECTRON TRANSISTOR
COULOMB-BLOCKADE
ANDERSON IMPURITY
ROOM-TEMPERATURE
TUNNEL-JUNCTIONS
EVEN NUMBER
MODEL
MAGNETORESISTANCE
OSCILLATIONS
CONDUCTANCE
Аннотация: By means of a diagram technique for Hubbard operators, we show the existence of a spin-dependent renormalization of the localized levels in an interacting region, e.g., quantum dot, modeled by the Anderson Hamiltonian with two conduction bands. It is shown that the renormalization of the levels with a given spin direction is due to kinematic interactions with the conduction subbands of the opposite spin. The consequence of this dressing of the localized levels is a drastically decreased tunneling current for ferromagnetically ordered leads compared to that of paramagnetically ordered leads. Furthermore, the studied system shows a spin-dependent resonant tunneling behavior for ferromagnetically ordered leads.
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