CAJ | 학술논문

采用推广的LLP方法研究了ZnSe/ZnS抛物量子阱中激子的极化子效应.考虑电子和空穴与LO声子的相互作用,得到了激子基态能量和结合能随阱宽的变化关系.结果表明,阱宽较小时,能量随着阱宽的增大而急剧减小;阱宽较大时,能量减小的比较缓慢.和我们以前的工作对比,我们发现ZnSe/ZnS抛物量子阱对激子的束缚强于GaAs/Ga1-xAlxAs抛物量子阱.
채용추엄적LLP방법연구료ZnSe/ZnS포물양자정중격자적겁화자효응.고필전자화공혈여LO성자적상호작용,득도료격자기태능량화결합능수정관적변화관계.결과표명,정관교소시,능량수착정관적증대이급극감소;정관교대시,능량감소적비교완만.화아문이전적공작대비,아문발현ZnSe/ZnS포물양자정대격자적속박강우GaAs/Ga1-xAlxAs포물양자정.
ZnSe-related quantum well structures have attracted much interest with regard to their optoelectronic application. They have large optical nonlinearity due to the large exciton binding energy compared with the IB-V compound semiconductors. The ZnSe/ZnS quantum well structure is a promising material for fabricating laser diodes since they have a direct band gap with wide band gap energy up to 3.75 eV at room temperature. The purpose of the present work is to investigate the polaron effects of the exciton in the ZnSe/ZnS parabolic quantum well (PQW). We assume the trial function has a simple form with the variables describing the motion within the quantum well plane separated from those describing the motion along the growth axis. The interaction of the charged particles with bulk longitudinal optical( LO) phonons is considered only, and the energy of the system is obtained by using a variational method developed by Lee, Low and Pines . The results showed that the ground state energy and the binding energy of the exciton with LO-phonon decrease rapidly with increasing the well width L at the beginning, then decreases very slowly with increasing L. In contrast to our previous work, it can be found that the exciton in the ZnSe/ZnS PQWs is more strongly bound than that in the GaAs/Ga1-XAlXAs PQWs.