Anisotropic optical polaron in crystals with complex structure

1995 ◽  
Vol 73 (3-4) ◽  
pp. 126-130 ◽  
Author(s):  
D. E. N. Brancus ◽  
A. C. Mocuta
Keyword(s):  
Effective Mass ◽  
Optical Phonon ◽  
Complex Structure ◽  
The Self ◽  
Coupling Theory ◽  
Phonon Interaction ◽  
Intermediate Coupling ◽  
Numerical Application ◽  
Self Energy ◽  
Mass Tensor

In the context of intermediate coupling theory, the forms of the self-energy and effective-mass tensor of the optical polaron, in appropriate uniaxial crystals with complex structure, are obtained. These forms contain all sources of anisotropy; the effective-mass tensor of the "bare" electron, the electron – optical-phonon interaction, and the angular dependence of the "true" phonoic modes. A numerical application is developed in the case of the CdS crystal.

EFFECTS OF CONFINED LO AND SO PHONON MODES ON POLARON IN FREESTANDING CYLINDRICAL QUANTUM WIRE WITH PARABOLIC CONFINEMENT

2009 ◽  
Vol 23 (29) ◽  
pp. 3515-3523 ◽  
Author(s):  
ANYUN ZOU ◽  
HONGJING XIE
Keyword(s):  
Effective Mass ◽  
Quantum Wire ◽  
Longitudinal Optical ◽  
Perturbation Approach ◽  
Wire Radius ◽  
Phonon Modes ◽  
Phonon Interaction ◽  
Electron Effective Mass ◽  
Self Energy ◽  
Parabolic Confinement

The electron self-energy and correction to the electron effective mass in a freestanding quantum wire with parabolic confining potential was investigated by the perturbation approach. Both the electron-confined longitudinal optical (LO) phonon and surface optical (SO) phonon interactions were considered. Results shows that, for small wire radius, the contributions of electron–LO phonon interaction to the electron self-energy and the correction to the electron effective mass are relatively small in compare with those of the electron–SO phonon interaction.

Piezoelectric Polaron Effects in Regular Crystals

1964 ◽  
Vol 19 (13) ◽  
pp. 1591-1598 ◽  
Author(s):  
Helmut Gabriel
Keyword(s):  
Effective Mass ◽  
Lattice Structure ◽  
Numerical Estimate ◽  
Wave Length ◽  
Approximate Solutions ◽  
The Self ◽  
Large Wave ◽  
Self Energy ◽  
Arbitrary Lattice ◽  
Pertubation Theory

Due to the interaction of an electron with both optical and acoustical modes in piezoelectric polar crystals, modified expressions for the self-energy and effective mass of the polaron are to be expected. The lattice vibrations are considered in the limit of large wave-length and an electrostatic approach to the interaction of charges in the lattice has been used. The HAMILTONIAN for a piezoelectric crystal of arbitrary lattice structure is given. With special reference to crystals of zincblende-type, approximate solutions for the self-energy and effective mass are found by thermodynamical pertubation theory. A numerical estimate for ZnS as a particularly favourable example, shows a negligible modification of the ground-state energy, but concerning the effective mass a contribution due to acoustical phonons of more than 50% of the optical-mode term.

The electron-phonon interaction, according to the adiabatic approximation

1956 ◽  
Vol 52 (4) ◽  
pp. 693-697 ◽  
Author(s):  
J. C. Taylor
Keyword(s):  
Adiabatic Approximation ◽  
Energy Levels ◽  
The Self ◽  
Electron Configuration ◽  
Phonon Interaction ◽  
Conduction Electrons ◽  
Electron Phonon Interaction ◽  
Self Energy

ABSTRACTThe interaction of conduction electrons with a vibrating metallic lattice has been considered by Ziman in terms of non-adiabatic perturbations to the adiabatic approximation of the Born-Oppenheimer theory. This programme is continued to calculate the self-energy of the electrons. When account is taken of the dependence of the energy levels of the adiabatic Hamiltonian itself upon the electron configuration, the final result is the same as the standard one.

The self-energy of a heavy quark in the gluonic vacuum and the effective mass

1983 ◽  
Vol 127 (3-4) ◽  
pp. 251-253 ◽  
Author(s):  
W. Ishizuka ◽  
Y. Kikuchi
Keyword(s):  
Heavy Quark ◽  
Effective Mass ◽  
The Self ◽  
Self Energy

Path Integral Calculations of Particle Self-Energy and Effective Mass in Coulomb Systems

1997 ◽  
Vol 11 (04) ◽  
pp. 129-138 ◽  
Author(s):  
V. Sa-Yakanit ◽  
V. D. Lakhno ◽  
Klaus Haß
Keyword(s):  
Effective Mass ◽  
Path Integral ◽  
State Energy ◽  
Coulomb Systems ◽  
Integral Approach ◽  
Coupling Region ◽  
Self Energy ◽  
Consistent Approximation ◽  
A Value ◽  
Wide Range

The generalized path integral approach is applied to calculate the ground state energy and the effective mass of an electron-plasmon interacting system for a wide range of densities. It is shown that in the self-consistent approximation an abrupt transition between the weak coupling and the strong coupling region of interaction exists. The transition occurs at low electron densities according to a value of 418 for rs, when Wigner crystallization is possible. For densities of real metals, the electron bandwidth is calculated and a comparison with experimental results is given.

scholarly journals Opacity from Loops in AdS

2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Alexandria Costantino ◽  
Sylvain Fichet
Keyword(s):  
Imaginary Part ◽  
Quantum Dynamics ◽  
Model Building ◽  
Asymptotic Properties ◽  
The Self ◽  
Effective Theory ◽  
Self Energy ◽  
Higher Dimensional ◽  
Timelike Region ◽  
Spectral Representations

Abstract We investigate how quantum dynamics affects the propagation of a scalar field in Lorentzian AdS. We work in momentum space, in which the propagator admits two spectral representations (denoted “conformal” and “momentum”) in addition to a closed-form one, and all have a simple split structure. Focusing on scalar bubbles, we compute the imaginary part of the self-energy ImΠ in the three representations, which involves the evaluation of seemingly very different objects. We explicitly prove their equivalence in any dimension, and derive some elementary and asymptotic properties of ImΠ.Using a WKB-like approach in the timelike region, we evaluate the propagator dressed with the imaginary part of the self-energy. We find that the dressing from loops exponentially dampens the propagator when one of the endpoints is in the IR region, rendering this region opaque to propagation. This suppression may have implications for field-theoretical model-building in AdS. We argue that in the effective theory (EFT) paradigm, opacity of the IR region induced by higher dimensional operators censors the region of EFT breakdown. This confirms earlier expectations from the literature. Specializing to AdS5, we determine a universal contribution to opacity from gravity.

scholarly journals Classical gravitational self-energy from double copy

2020 ◽  
Vol 2020 (11) ◽  
Author(s):  
Gabriel Luz Almeida ◽  
Stefano Foffa ◽  
Riccardo Sturani
Keyword(s):  
Gravitational Field ◽  
Binary System ◽  
The Self ◽  
Gravitational Coupling ◽  
Leading Order ◽  
Body System ◽  
Self Energy ◽  
Composite Systems ◽  
Body Dynamics ◽  
Double Copy

Abstract We apply the classical double copy to the calculation of self-energy of composite systems with multipolar coupling to gravitational field, obtaining next-to-leading order results in the gravitational coupling GN by generalizing color to kinematics replacement rules known in literature. When applied to the multipolar description of the two-body system, the self-energy diagrams studied in this work correspond to tail processes, whose physical interpretation is of radiation being emitted by the non-relativistic source, scattered by the curvature generated by the binary system and then re-absorbed by the same source. These processes contribute to the conservative two-body dynamics and the present work represents a decisive step towards the systematic use of double copy within the multipolar post-Minkowskian expansion.

Electron‐optical‐phonon interaction in binary/ternary heterostructures

1990 ◽  
Vol 68 (12) ◽  
pp. 6289-6292 ◽  
Author(s):  
K. W. Kim ◽  
M. A. Stroscio
Keyword(s):  
Optical Phonon ◽  
Phonon Interaction

scholarly journals ON THE PHONON-INDUCED SUPERCONDUCTIVITY OF DISORDERED ALLOYS

1996 ◽  
Vol 10 (20) ◽  
pp. 2469-2529 ◽  
Author(s):  
A.O. ANOKHIN ◽  
M.I. KATSNELSON
Keyword(s):  
Effective Interaction ◽  
Energy Scale ◽  
Phonon Interaction ◽  
Interaction Kernel ◽  
Generating Functional ◽  
Electron Phonon Interaction ◽  
Self Energy ◽  
Disordered Alloys ◽  
Electron Phonon Coupling ◽  
Alloy Part

A model of alloy is considered which includes both quenched disorder in the electron subsystem (“alloy” subsystem) and electron-phonon interaction. For given approximate solution for the alloy part of the problem, which is assumed to be conserving in Baym’s sense, we construct the generating functional and derive the Eliashberg-type equations which are valid to the lowest order in the adiabatic parameter. The renormalization of bare electron–phonon interaction vertices by disorder is taken into account consistently with the approximation for the alloy self-energy. For the case of exact configurational averaging the same set of equations is established within the usual T-matrix approach. We demonstrate that for any conserving approximation for the alloy part of the self-energy the Anderson’s theorem holds in the case of isotropic singlet pairing provided disorder renormalizations of the electron-phonon interaction vertices are neglected. Taking account of the disorder renormalization of the electron-phonon interaction we analyze general equations qualitatively and present the expressions for Tc for the case of weak and intermediate electron-phonon coupling. Disorder renormalizations of the logarithmic corrections to the effective coupling, which arise when the effective interaction kernel for the Cooper channel has the second energy scale, as well as the renormalization of the dilute paramagnetic impurity suppression are discussed.

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