温度和极化子效应对准二维强耦合激子基态的影响

Influences of temperature and polaron effect on the ground state of quasi-two-dimensional strong-coupling exciton

采用Huybrechts线性组合算符和Lee-Low-Pines变换法研究了温度和极化子效应对量子阱中激子与界面光学声子强耦合又与体纵光学声子弱耦合体系基态的影响,推导出激子基态的诱生势和基态能量的移动的表达式.以AgCl/AgBr量子阱为例进行了数值计算,结果表明,由激子-界面光学声子强耦合所产生的激子基态的诱生势和基态能量的移动随温度的升高而增大,而由激子-体纵光学声子弱耦合所产生的激子基态的诱生势和基态能量的移动随温度的升高而减小.

The influences of temperature and polaron effect on the ground state of the system, for which the exciton is strongly coupled with interface-optical （IO） phonons but weakly coupled with bulk-longitudinal-optical （LO） phonons in a quantum well, are studied by using the Huybrechts＇ linear-combination operator and Lee-Low-Pines （LLP） transformation method. The expressions for the induced potential and energy shift of the ground state of the exciton were derived. Numerical calculations for AgC1/AgBr QW, as an example, are performed. The result indicates that the induced potential and the energy shift increases for strong exciton-IO-phonon coupling but decreases for weak exciton-LO-phonon coupling with temperature.