D-Ground State Binding Energy in Graded GaAs-(Ga,Al)As Quantum Well

2000 ◽  
Vol 220 (1) ◽  
pp. 171-174 ◽  
Author(s):  
I.D. Mikhailov ◽  
F.J. Betancur ◽  
J.H. Marín
2019 ◽  
Vol 33 (21) ◽  
pp. 1950239 ◽  
Author(s):  
Xiu-Qing Wang ◽  
Ying-Jie Chen ◽  
Jing-Lin Xiao

The ground state binding energy (E[Formula: see text]) and the mean number of LO phonons (N) of the strong-coupling magneto-polaron (SCMP) in an asymmetrical semi-exponential quantum well (ASEQW) are studied theoretically. Temperature (T) effects on E[Formula: see text] and N are acquired with the quantum statistics theory (QST). By using the Lee-Low-Pines unitary transformation (LLPUT) and linear combination operation method (LCOM), the variations of E[Formula: see text] and N with T and [Formula: see text] of magnetic field are discussed. The investigated results indicate that both T and [Formula: see text] have great influence on E[Formula: see text] and N of LO phonons.


2021 ◽  
pp. 2150273
Author(s):  
Saren Gaowa ◽  
Xiu-Juan Miao ◽  
Jing-Lin Xiao ◽  
Cui-Lan Zhao

This paper utilized the methods of linear combination and unitary transformation to evaluate the vibrational frequency (VF) and ground state binding energy (GSBE) of a strong-coupling magnetopolaron in an asymmetrical Gaussian potential quantum well (AGPQW), and the effects of the temperature on these physical quantities were studied through quantum statistical theory. The changes of the VF and GSBE versus temperature and cyclotron frequency (CF) in a magnetic field were discussed. The numerical calculations revealed that with the increase of temperature, the VF and GSBE also increased. Meanwhile, the numerical results show that the VF increases with the increase of the CF. However, the GSBE versus the CF has different changing properties.


2008 ◽  
Vol 22 (12) ◽  
pp. 1923-1932
Author(s):  
JIA LIU ◽  
ZI-YU CHEN

The influence of a perpendicular magnetic field on a bound polaron near the interface of a polar–polar semiconductor with Rashba effect has been investigated. The material is based on a GaAs / Al x Ga 1-x As heterojunction and the Al concentration varying from 0.2 ≤ x ≤ 0.4 is the critical value below which the Al x Ga 1-x As is a direct band gap semiconductor.The external magnetic field strongly altered the ground state binding energy of the polaron and the Rashba spin–orbit (SO) interaction originating from the inversion asymmetry in the heterostructure splitting of the ground state binding energy of the bound polaron. How the ground state binding energy will be with the change of the external magnetic field, the location of a single impurity and the electron area density have been shown in this paper, taking into account the SO coupling. The contribution of the phonons are also considered. It is found that the spin-splitting states of the bound polaron are more stable, and, in the condition of weak magnetic field, the Zeeman effect can be neglected.


Author(s):  
Feng Qi Zhao ◽  
Zi Zheng Guo ◽  
Bo Zhao

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.


1989 ◽  
Vol 67 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Magne Haugen ◽  
Erlend Østgaard

The ground-state energy of spin-polarized hydrogen, deuterium, and tritium is calculated by means of a modified variational lowest order constrained-variation method, and the calculations are done for five different two-body potentials. Spin-polarized H↓ is not self-bound according to our theoretical results for the ground-state binding energy. For spin-polarized D↓, however, we obtain theoretical results for the ground-state binding energy per particle from −0.42 K at an equilibrium particle density of 0.25 σ−3 or a molar volume of 121 cm3/mol to + 0.32 K at an equilibrium particle density of 0.21 σ−3 or a molar volume of 142 cm3/mol, where σ = 3.69 Å (1 Å = 10−10 m). It is, therefore, not clear whether spin-polarized deuterium should be self-bound or not. For spin-polarized T↓, we obtain theoretical results for the ground-state binding energy per particle from −4.73 K at an equilibrium particle density of 0.41 σ−3 or a molar volume of 74 cm3/mol to −1.21 K at an equilibrium particle density of 0.28 σ−3 or a molar volume of 109 cm3/mol.


2016 ◽  
Vol 954 ◽  
pp. 149-160 ◽  
Author(s):  
F. Schulz ◽  
P. Achenbach ◽  
S. Aulenbacher ◽  
J. Beričič ◽  
S. Bleser ◽  
...  

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