摘要
在 77 K下用N_2激光器的 337.1nm脉冲激光线作为激发源,研究了高激发密度下ZnSe-ZnS/CaF_2超晶格的自由激子发光特性及激子的光学非线性.对于该超晶格体系,首次观察到激子-激子散射发光,激子饱和吸收及光学双稳现象.并根据激子态的填充效应很好地解释了实验中观察到的随激发光强增加出现激子发光和吸收的蓝移现象.
The free exciton emission and optical nonlinearities in ZnSe-ZnS grown by MOCVD onCaF_2 substrates have been studied under different excitation densities at 77K.We report thefirst observation of the new emission band due to Ex-Ex interaction, exciton saturating absorp-tion and exciton optical bistability in ZnSe-ZnS/CaF_2 superlattices.The dominant exciton opti-cal nonlinear mechanism for ZnSe-ZnS/CaF_2 superlattices under high excitation density is thecombination of phase space filling of exciton state and exciton band broadening.
关键词
ZnSe-ZnS/CaF
超晶格
激子光学
Laser Beams
Applications
Lasers
Materials
Superlattices
Optical Properties
