Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Photon echo in direct-gap semiconductors
Indrani Majumdar, Pranay K. Sen
Abstract
Based upon the time dependent perturbation theory for coherent radiation-semiconductor interaction, the possibility of occurrence of the phenomenon of two-pulse photon echo has been investigated analytically in a bulk direct-gap semiconductor under near resonant transition regime below the absorption edge of the crystal. The excitation intensity is chosen to be in the low-to-moderate power regime such that the photoinduced electron-hole pair density remains below the Mott transition limit and the weakly bound Wannier-Mott excitonic structure of the crystal absorption edge is manifested. The band gap renormalization effect is also taken into account. Numerical estimation of the transmitted intensity has been made for electron-hole transition to the 1s excitonic states in the bulk CdS crystal. The analytical results demonstrate the occurrence of photon echo in direct-gap semiconductors.