Bound-polaron model of effective-mass binding energies in GaN

1998 ◽  
Vol 57 (15) ◽  
pp. 8951-8956 ◽  
Author(s):  
Stephen A. McGill ◽  
Ke Cao ◽  
W. Beall Fowler ◽  
Gary G. DeLeo
Keyword(s):  
Effective Mass ◽  
Binding Energies ◽  
Polaron Model ◽  
Bound Polaron

EFFECTIVE MASS OF STRONG-COUPLED BOUND POLARON IN AN ASYMMETRIC QUANTUM DOT INDUCED WITH RASHBA EFFECT

2011 ◽  
Vol 10 (03) ◽  
pp. 501-505 ◽  
Author(s):  
ZHIXIN LI ◽  
JUAN XIAO ◽  
AIYONG LIU ◽  
JINGLIN XIAO
Keyword(s):  
Quantum Dot ◽  
Effective Mass ◽  
Operator Method ◽  
Transformation Method ◽  
Rashba Effect ◽  
Linear Combination Operator ◽  
Polaron Model ◽  
Bound Polaron ◽  
Asymmetric Quantum Dot ◽  
Asymmetric Quantum

In this paper, on the basis of Huybrechs' strong-coupled polaron model, the Tokuda-modified linear-combination operator method and the unitary transformation method are used to study the properties of the strong-coupled bound polaron considering the influence of Rashba effect, which is brought by the spin-orbit (SO) interaction, in an asymmetric quantum dot (QD). The expression for the effective mass of the polaron as functions of the transverse and longitudinal bound strengths, velocity, vibration frequency, and the bound potential has been derived. After a simple numerical calculation on the RbCl crystal, we found that the total effective mass of the bound polaron is composed of three parts. The interaction between the orbit and the spin with different directions has different effects on the effective mass of the bound polaron.

First-excited-state energy of hydrogenic impurity bound polaron in an anisotropic quantum dot in an electric field

2019 ◽  
Vol 33 (32) ◽  
pp. 1950386
Author(s):  
Shi-Hua Chen
Keyword(s):  
Excited State ◽  
Binding Energy ◽  
Quantum Dot ◽  
Electric Field ◽  
Binding Energies ◽  
Hydrogenic Impurity ◽  
Bound Polaron ◽  
First Excited State ◽  
Trial Wavefunction ◽  
Anisotropic Quantum Dot

The first-excited-state (ES) binding energy of hydrogenic impurity bound polaron in an anisotropic quantum dot (QD) is obtained by constructing a variational wavefunction under the action of a uniform external electric field. As for a comparison, the ground-state (GS) binding energy of the system is also included. We apply numerical calculations to KBr QD with stronger electron–phonon (E–P) interaction in which the new variational wavefunction is adopted. We analyzed specifically the effects of electric field and the effects of both the position of the impurity and confinement lengths in the xy-plane and the [Formula: see text] direction on the ground and the first-ES binding energies (BEs). The results show that the selected trial wavefunction in the ES is appropriate and effective for the current research system.

A Unified Treatment of The Thermal Donor Hierarchies in Silicon and Germanium

1985 ◽  
Vol 59 ◽  
Author(s):  
Jeffrey T. Borenstein ◽  
James W. Corbett
Keyword(s):  
Dielectric Constant ◽  
Effective Mass ◽  
Ground State ◽  
Shallow Donor ◽  
Binding Energies ◽  
Electron Effective Mass ◽  
Perturbation Model ◽  
Thermal Donor ◽  
Silicon And Germanium ◽  
Oxygen Atoms

ABSTRACTThe hierarchies of thermal donor binding energies produced by annealing oxygen-containing silicon or germanium at ca. 450°C are explained by using a generalized perturbation model which involves a standard repulsion parameter for the interaction between agglomerating oxygen atoms and the shallow donor electrons. This model is capable of fitting the ground state ladders for both charge states of the thermal donors in both Si and Ge, since differences between the two ladders can–ee explained entirely by the change in the electron-effective-mass and dielectric constant of the host.

Bound polaron in a narrow-band polar crystal

1993 ◽  
Vol 71 (11-12) ◽  
pp. 493-500
Author(s):  
Y. Lépine ◽  
O. Schönborn
Keyword(s):  
Effective Mass ◽  
Ground State ◽  
Narrow Band ◽  
Wave Functions ◽  
Phonon Coupling ◽  
Polar Crystal ◽  
Bound Polaron ◽  
Narrow Bandwidth ◽  
Electron Phonon Coupling ◽  
Shallow Impurities

The ground-state energy of a bound polaron in a narrow-band polar crystal (such as a metal oxide) is studied using variational wave functions. We use a Fröhlich-type Hamiltonian on which the effective mass approximation has not been effected and in which a Debye cutoff is made on the phonon wave vectors. The wave functions that are used are general enough to allow the existence of a band state and of a self-trapped state and are reliable in the nonadiabatic limit. We find that three ground states are possible for this system. First, for small electron–phonon coupling, moderate bandwidth, and shallow impurities, the usual effective-mass hydrogenic ground state is found. For a narrow bandwidth and a deep defect, a collapsed state is predicted in which the polaron coincides with the position of the defect. Finally, for moderate electron–phonon coupling, narrow bandwidth, and a very weak defect, a self-trapped polaron in a hydrogenic state is predicted. Our conclusions are presented as asymptotic expansions and as phase diagrams indicating the values of the parameters for which each phase can be found.

THE EFFECTIVE MASS OF STRONG-COUPLED POLARON IN AN ASYMMETRIC QUANTUM DOT INDUCED WITH RASHBA EFFECT

2010 ◽  
Vol 24 (23) ◽  
pp. 2423-2430 ◽  
Author(s):  
ZHI-XIN LI ◽  
JING-LIN XIAO ◽  
HONG-YAN WANG
Keyword(s):  
Quantum Dot ◽  
Effective Mass ◽  
Unitary Transformation ◽  
Spin Orbit ◽  
Rashba Effect ◽  
Linear Combination Operator ◽  
Polaron Model ◽  
Asymmetric Quantum Dot ◽  
Asymmetric Quantum ◽  
Transformation Methods

In this paper, on the basis of Huybrechs' strong-coupled polaron model, Tokuda modified linear-combination operator and the unitary transformation methods are used to study the properties of the strong-coupled polaron considering the influence of Rashba effect, which is brought by the spin-orbit (SO) interaction, in the asymmetric quantum dot (QD). The expressions of the effective mass as a function of the transverse and longitudinal confinement strengths, the velocity and the vibration frequency were derived. Numerical calculation on the RbCl QD, as an example, is performed and the results show that the total effective mass of the polaron is composed of three parts. The interaction between the orbit and the spin with different directions has different effects on the effective mass of the polaron.

Donor States in Spherical GaAs-Ga1-xAlxAs Quantum Dots

1997 ◽  
Vol 11 (15) ◽  
pp. 673-679 ◽  
Author(s):  
Ecaterina C. Niculescu ◽  
Ana Niculescu
Keyword(s):  
Quantum Dots ◽  
Quantum Dot ◽  
Effective Mass ◽  
Coulomb Potential ◽  
Adjustable Parameter ◽  
Binding Energies ◽  
Central Cell ◽  
Shallow Donors ◽  
Mass Approximation ◽  
Donor States

The effect of the central cell correction on the binding energies of shallow donors in a spherical GaAs-Ga 1-x Al x As quantum dot is studied. The effective-mass approximation within a variational scheme is adopted and central cell corrections are calculated by using a Coulomb potential modified with an adjustable parameter. For small values of the radius of the dot large corrections are obtained for the shallow donors studied.

Bistable behavior of the nitrogen impurity in SiC nanoclusters

Nanoscale ◽  
2020 ◽  
Vol 12 (21) ◽  
pp. 11536-11555
Author(s):  
T. L. Petrenko ◽  
V. P. Bryksa ◽  
T. T. Petrenko
Keyword(s):  
Effective Mass ◽  
Bistable Behavior ◽  
Bound Polaron ◽  
Nitrogen Impurity

Bistable behavior and coexistence of effective mass, small bound polaron and DX-like states of the nitrogen impurity in SiC nanoclusters.

The Fröhlich Hamiltonian: mathematical results. III. Perturbation theory

1979 ◽  
Vol 57 (2) ◽  
pp. 114-119
Author(s):  
Bernard M. de Dormale
Keyword(s):  
Perturbation Theory ◽  
Effective Mass ◽  
Energy Shift ◽  
Simplified Model ◽  
Polaron Model ◽  
Exact Eigenvalue ◽  
Eigenvalue And Eigenvector

We prove the validity of perturbation theory for the polaron model. After obtaining the usual results for the Hamiltonian without cut-off, we derive the effective mass and energy shift for the Hamiltonian with cut-off. We also introduce a simplified model whose exact eigenvalue and eigenvector can be computed.

EFFECTIVE MASSES FOR DONOR BINDING ENERGIES IN QUANTUM WELL SYSTEMS

2006 ◽  
Vol 20 (24) ◽  
pp. 1529-1541 ◽  
Author(s):  
S. RAJASHABALA ◽  
K. NAVANEETHAKRISHNAN
Keyword(s):  
Quantum Well ◽  
Effective Mass ◽  
Binding Energies ◽  
Bohr Radius ◽  
Mass Variation ◽  
Effective Masses ◽  
Approximate Form ◽  
Finite Barrier ◽  
Infinite Barrier ◽  
Barrier Model

The donor ionization energies in a quantum well and quantum dot with finite and infinite barriers are estimated for different well dimensions. Using the effective mass (EM) approximation, calculations are presented with constant effective mass and position dependent effective masses that are different for finite and infinite cases. Our results reduce to an approximate form used by X. H. Qi et al., Phys. Rev. B58 (1998) 10578 in the finite barrier model and that of L. E. Oliveira and L. M. Falicov, Phys. Rev. B34 (1986) 8676 in the infinite barrier case. Results are presented by taking the GaAs quantum well as an example. The use of constant effective mass of 0.067m0 is justified for well dimensions ≥a* where a* is an effective Bohr radius which is about 100 Å. While Qi et al. found a maximum of 22% variation in the binding energies due to mass variation, we obtained nearly 100% variation when mass variations are included correctly.

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