Effects of localized phonon modes on magnetotunneling spectra in double-barrier structures

1991 ◽  
Vol 44 (23) ◽  
pp. 12959-12963 ◽  
Author(s):  
P. J. Turley ◽  
S. W. Teitsworth
Keyword(s):  
Phonon Modes ◽  
Double Barrier

TRANSFER MATRIX METHOD FOR ELECTRON-IO-PHONON INTERACTION IN ASYMMETRIC DOUBLE-BARRIER STRUCTURES

2001 ◽  
Vol 15 (27) ◽  
pp. 3539-3549 ◽  
Author(s):  
ZU WEI YAN ◽  
X. X. LIANG
Keyword(s):  
Transfer Matrix ◽  
Transfer Matrix Method ◽  
Matrix Method ◽  
Phonon Modes ◽  
Phonon Interaction ◽  
Double Barrier ◽  
Long Wavelength ◽  
Dielectric Continuum ◽  
Modes Coupling ◽  
Dielectric Continuum Model

Within the framework of the dielectric continuum model, the interface-optical (IO) phonon modes and their interaction with electrons in an asymmetric double-barrier structure is studied by using a transfer matrix method. The dispersion equation of IO phonon modes and the electron-IO-phonon (e-IO-p) interaction Hamiltonian are derived. It is found that there are eight branches of IO-phonon modes coupling with electrons besides the confined LO-phonon modes. The numerical results are obtained for several GaAs/Al x Ga 1-x As systems. It is seen that the contributions of long-wavelength phonons to the e-IO-p coupling are important. The e-IO-p coupling related to the IO modes with the GaAs LO-frequency (phonon energy 36.25 meV) at the long-wavelength limit is strongest in the eight branches of IO-phonon modes.

PHONON REPLICA IN THE I–V CHARACTERISTICS OF A GaAs/AlGaAs DOUBLE-BARRIER STRUCTURE

1993 ◽  
Vol 07 (19) ◽  
pp. 3449-3460 ◽  
Author(s):  
NANZHI ZOU ◽  
J. RAMMER ◽  
K.A. CHAO
Keyword(s):  
Detailed Calculation ◽  
Barrier Structure ◽  
Phonon Modes ◽  
Double Barrier ◽  
Phonon Replica ◽  
Double Barrier Structure ◽  
Asymmetric Barriers

We have performed a detailed calculation of the I–V characteristic of a GaAs/Al x Ga 1−x As double barrier structure, with special emphasis on the phonon replica. For commonly used experimental samples (x≃0.3–0.4), the interface-like phonon modes produced by alloying and localized in barriers near the interfaces give the dominating contribution to the phonon replica. Our calculated I–V curves for samples of both symmetric and asymmetric barriers with or without bistability agree extremely well with experimental observations.

scholarly journals Coherent and Phonon-assisted Tunnelling in Asymmetric Double Barrier Resonant Tunnelling Structures

2000 ◽  
Vol 53 (1) ◽  
pp. 35
Author(s):  
Jun-jie Shi ◽  
B. C. Sanders ◽  
Shao-hua Pan
Keyword(s):  
Phonon Scattering ◽  
Electron Interaction ◽  
Phonon Modes ◽  
Double Barrier ◽  
Resonant Level ◽  
Resonant Tunnelling ◽  
Improved Performance ◽  
Tunnelling Current ◽  
Peak Value ◽  
Interface Phonons

We present a theory for calculating the phonon-assisted tunnelling current in asymmetric double barrier resonant tunnelling structures (DBRTS), in which all of the phonon modes including the interface modes and the confined bulk-like LO phonons and the conduction band nonparabolicity are considered. An important physical picture about coherent and phonon-assisted tunnelling is given. The coherent tunnelling current can be directly determined by both the width of the resonant level and the peak value of the transmission coecient at the resonant level. The phonon-assisted tunnelling current mainly comes from electron interaction with higher frequency interface phonons (especially the interface phonons localised at either interface of the left barrier). Phonon-assisted tunnelling makes a significant contribution to the valley current. The subband nonparabolicity strongly influences on electron?phonon scattering and current-to-voltage characteristics. A specially designed asymmetric DBRTS may have an improved performance over the symmetric DBRTS.

Resonant tunnelling in AlInas/GaInAs double barrier diodes grown by MOCVD

1988 ◽  
Vol 24 (3) ◽  
pp. 187 ◽  
Author(s):  
P.D. Hodson ◽  
D.J. Robbins ◽  
R.H. Wallis ◽  
J.I. Davies ◽  
A.C. Marshall
Keyword(s):  
Double Barrier ◽  
Resonant Tunnelling

scholarly journals Phonons in Short-Period GaN/AlN Superlattices: Group-Theoretical Analysis, Ab initio Calculations, and Raman Spectra

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 286
Author(s):  
Valery Davydov ◽  
Evgenii Roginskii ◽  
Yuri Kitaev ◽  
Alexander Smirnov ◽  
Ilya Eliseyev ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Raman Spectra ◽  
Density Functional ◽  
Structural Characteristics ◽  
Vibrational Modes ◽  
Phonon Modes ◽  
Short Period ◽  
Group Theoretical Analysis

We report the results of experimental and theoretical studies of phonon modes in GaN/AlN superlattices (SLs) with a period of several atomic layers, grown by submonolayer digital plasma-assisted molecular-beam epitaxy, which have a great potential for use in quantum and stress engineering. Using detailed group-theoretical analysis, the genesis of the SL vibrational modes from the modes of bulk AlN and GaN crystals is established. Ab initio calculations in the framework of the density functional theory, aimed at studying the phonon states, are performed for SLs with both equal and unequal layer thicknesses. The frequencies of the vibrational modes are calculated, and atomic displacement patterns are obtained. Raman spectra are calculated and compared with the experimental ones. The results of the ab initio calculations are in good agreement with the experimental Raman spectra and the results of the group-theoretical analysis. As a result of comprehensive studies, the correlations between the parameters of acoustic and optical phonons and the structure of SLs are obtained. This opens up new possibilities for the analysis of the structural characteristics of short-period GaN/AlN SLs using Raman spectroscopy. The results obtained can be used to optimize the growth technologies aimed to form structurally perfect short-period GaN/AlN SLs.

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