Free polaron energy levels in AlyGa1−yN/AlxGa1−xN triangle quantum well structures

In this work, a variational method is used to examine the problems relevant to the free polaron energy spectrum in a wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangle quantum well structure. The numerical calculations for the ground state energy, transition energy and polaron energy shifts as the functions of well-width [Formula: see text] and composition [Formula: see text] are carried out by considering the anisotropies of the parameters, such as the optical phonon frequency, dielectric constant and electron effective mass, as well as their observed changes with coordinate [Formula: see text] in this system. The research results show that the polaron energy shift caused by the electron–optical phonon interaction is large, and leads to an obvious energy decrease in the Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangular quantum well structure. The contribution of the confined phonon is found to increase with the increasing of the well-width and composition [Formula: see text], while that of the half space phonon is observed to decrease with the increasing of the well-width and composition [Formula: see text]. The total contribution of the phonon increases with the increasing composition [Formula: see text], while a minimum is found to occur to the total contribution of the phonon during the decreasing process with the well-width. As the [Formula: see text] increases, the free polaron energies and transition energies decrease. Meanwhile, with the increasing of the composition [Formula: see text], the energy and transition energy are found to be increased. In the Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangular quantum well structure, the trends of the free polaron energy, transition energy and polaron energy shifts with the well-width and composition [Formula: see text] are found to be similar to those in the GaN/Al[Formula: see text]Ga[Formula: see text]N square quantum well structure. However, the corresponding values in the triangular quantum well structure are obviously greater than those in the square quantum well structure.

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The effect of electron effective mass mismatch on the electron - optical-phonon scattering rate in a quantum well structure

Semiconductor Science and Technology ◽

10.1088/0268-1242/12/10/010 ◽

1997 ◽

Vol 12 (10) ◽

pp. 1235-1239 ◽

Cited By ~ 5

Author(s):

Yisong Zheng ◽

Tianquan Lü ◽

Jiang Liu ◽

Wenhui Su

Keyword(s):

Quantum Well ◽

Effective Mass ◽

Optical Phonon ◽

Phonon Scattering ◽

Electron Effective Mass ◽

Quantum Well Structure ◽

Scattering Rate ◽

Optical Phonon Scattering

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Influence of Pressure on Polaron Energy in a Wurtzite GaN/AlxGa1-xN Quantum Well

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.288.17 ◽

2019 ◽

Vol 288 ◽

pp. 17-26

Author(s):

Feng Qi Zhao ◽

Xiao Mei Dai

Keyword(s):

Hydrostatic Pressure ◽

Quantum Well ◽

Quantum Wells ◽

Half Space ◽

Ground State Energy ◽

Ground State ◽

State Energy ◽

Transition Energy ◽

Total Contribution ◽

Polaron Energy

The influence of hydrostatic pressure on the polaron energy level in wurtzite GaN/AlxGa1-xN quantum well is studied by a Lee-Low-Pines variational method, and the numerical results of the ground state energy, transition energy and contributions of different phonons to polaron energy (polaron effects) are given as functions of pressurepand compositionx. The results show that the ground state energy and transition energy in the wurtzite GaN/AlxGa1-xN quantum well decrease with the increase of the hydrostatic pressurep, and increase with the increase of the compositionx. The contributions of different phonons to polaron energy with pressurepand compositionxare obviously different. With the increase of hydrostatic pressure, the contribution of half-space phonon, confined phonon and the total contribution of phonons of all branches increases obviously, while the contribution of interface phonon slowly increases. During the increase of the composition, the contribution of interface phonon decreases and the contribution of half-space phonon increases slowly, while the contribution of confined phonon and the total contribution of phonons increases significantly. In general, the electron-optical phonon interaction play an important role in electronic states of GaN/AlxGa1-xN quantum wells and can not be neglected.

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Time-Resolved Raman Studies of Electron-Optical Phonon Interactions in GaAs-AlAs Multiple Quantum Well Structures

Phonons in Semiconductor Nanostructures ◽

10.1007/978-94-011-1683-1_19 ◽

1993 ◽

pp. 195-203

Author(s):

K. T. Tsen ◽

C. Chia ◽

Keith R. Wald ◽

Tobias Ruf ◽

Peter Y. Yu ◽

...

Keyword(s):

Quantum Well ◽

Optical Phonon ◽

Multiple Quantum Well ◽

Multiple Quantum ◽

Time Resolved ◽

Quantum Well Structures

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Electron–optical–phonon scattering in non-square quantum-well structures

Solid State Communications ◽

10.1016/s0038-1098(00)00010-7 ◽

2000 ◽

Vol 114 (2) ◽

pp. 101-106 ◽

Cited By ~ 5

Author(s):

Wenhui Duan ◽

Jia-Lin Zhu ◽

Bing-Lin Gu ◽

Jian Wu

Keyword(s):

Quantum Well ◽

Optical Phonon ◽

Phonon Scattering ◽

Quantum Well Structures ◽

Optical Phonon Scattering

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Electron-optical phonon interaction and in-plane mobility in lead chalcogenide quantum-well structures

Physical Review B ◽

10.1103/physrevb.59.15312 ◽

1999 ◽

Vol 59 (23) ◽

pp. 15312-15322 ◽

Cited By ~ 1

Author(s):

Victor Bondarenko

Keyword(s):

Quantum Well ◽

Optical Phonon ◽

Lead Chalcogenide ◽

Phonon Interaction ◽

Quantum Well Structures

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The effect of hydrostatic pressure on binding energy and polaron effect of bound polaron in wurtzite AlyGa1−yN/AlxGa1−xN parabolic quantum well

International Journal of Modern Physics B ◽

10.1142/s0217979221500089 ◽

2020 ◽

pp. 2150008

Author(s):

Feng Qi Zhao ◽

Zi Zheng Guo ◽

Bo Zhao

Keyword(s):

Hydrostatic Pressure ◽

Binding Energy ◽

Quantum Well ◽

Optical Phonon ◽

Ground State ◽

Phonon Interaction ◽

Polaron Effect ◽

Bound Polaron ◽

Composition Formula ◽

Effect Of Hydrostatic Pressure

The effect of hydrostatic pressure on binding energy and polaron effect of the bound polaron in a wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N parabolic quantum well (QW) is studied using the Lee–Low–Pines intermediate coupling variational method in the paper. The numerical relationship of binding energy and polaron effect of the bound polaron are given as a functions of pressure [Formula: see text], composition [Formula: see text] and well width [Formula: see text]. In the theoretical calculations, the anisotropy of the electron effective band mass, the optical phonon frequency, the dielectric constant and other parameters in the system varying with the pressure [Formula: see text] and the coordinate [Formula: see text] are included. The electron–optical phonon interaction and the impurity center–optical phonon interaction are considered. The results show that hydrostatic pressure has a very obvious effect on binding energy and polaron effect of the bound polaron in the wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N parabolic QW. For QWs with determined structural parameters, the contributions of the three branch of phonons, i.e., the confined (CF) phonon, half-space (HS) phonon and the interface (IF) phonon, to binding energy of the polaron increase with the increase of the pressure [Formula: see text], the CF phonons contribute the most. Under the condition of a certain well width and hydrostatic pressure, with the increase of the composition [Formula: see text], the ground state binding energy of the bound polaron in the wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N parabolic QW increases, and the contribution of the IF phonon and HS phonons to the binding energy decreases, while the contribution of the CF phonons and the total contribution of all phonons increase significantly. In the wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N parabolic QW, the ground state binding energy of the bound polaron decreases with the increase of the well width. The decrease rate is greater in the narrow well, and smaller in the wide well. The contribution of different branches of phonons to binding energy varies with the change of the well width. With the increase of the well width, the contribution of CF phonons to binding energy increases, the contribution of HS phonons to binding energy decreases, and the IF phonon contribution and the total phonon contribution first increase to the maximum value and then gradually decrease slightly. The changing trend of binding energy of bound polaron in the wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N parabolic QW, of the contribution of different branch phonons to binding energy with the pressure [Formula: see text], composition [Formula: see text] and well width [Formula: see text] is similar to that of the GaN/Al[Formula: see text]Ga[Formula: see text]N square QW, but the change in the parabolic QW is more obvious.

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