各向异性抛物势对非对称半指数量子阱中杂质极化子基态能量的影响

The effects of an anisotropic parabolic potential on the ground state energy of impurity-polaron in asymmetrical semi-exponential quantum wells

当非对称半指数量子阱中在阱的生长方向存在非对称半指数受限势,而在垂直于阱的生长方向存在各向异性抛物受限势时,我们理论上研究了类氢杂质対非对称半指数量子阱中弱耦合杂质极化子基态能量性质的影响.应用线性组合算符方法和两次幺正变换导出了非对称半指数量子阱中弱耦合杂质极化子的基态能量.我们挑选非对称半指数GaAs半导体量子阱晶体为例,计算了非对称半指数量子阱中弱耦合杂质极化子的基态能量与库仑杂质势的强度,非对称半指数受限势的两个正参数和x方向和y方向的各向异性抛物势的受限强度变换关系.通过数值我们发现非对称半指数量子阱中弱耦合杂质极化子的基态能量随库仑杂质势的强度的增加而增大,杂质极化子的基态能量是参量U和x方向和y方向的各向异性抛物势的受限强度的的增函数,而它是参量σ的减函数.表现了奇特的量子尺寸限制效应.

When asymmetrical semi-exponential(ASE)GaAs quantum well(GW)with an asymmetrical semi-exponential potential(ASEP)in the QW’s growth direction and with an anisotropic parabolic potential(APP)perpendicular to the QW’s growth direction,we have studied the influences of the hydrogen-like impurity on the properties of the ground state energy of the weak-coupling impurity-polaron in a GaAs asymmetrical semi-exponential quantum wells(ASEQW)s.By employing linear combination operator and the quadratic unitary transformations methods,the ground state energy of the weak-coupling impurity-polaron in an ASEQWs have been derived.Taking the GaAs ASE confinement potential well semiconductor crystals as example,we calculated the ground state energy of the weak-coupling impurity-polaron in a GaAs ASEQWs varying with the strength of the Coulombic impurity potential,the two parameters of the ASE confinement potential and the confinement strengths of an anisotropic parabolic confinement potential in the x and y directions.According to the obtained results,it is found that the ground state energy of the weak-coupling impurity-polaron in an ASEQW elevates with lifting the confinement strengths of an anisotropic parabolic confinement potential in the x and y directions and the parameter U,whereas it elevates with decaying the other parameterσand the strength of the Coulombic impurity potential.These results can be attributed to the interesting quantum size confining effects.