Photoluminescence excitation spectra of CuInS_(2) crystals

摘要

The photoluminescence excitation (PLE) spectra of CuInS_(2) crystals grown by the traveling heater method (THM) and the iodine vapor transport method (IT) have been examined. THM crystals show significant structure with many peaks and dips in the PLE spectra, whereas IT crystals exhibits two clear peaks at two free exciton energies in the spectrum. The peak and dip structures of PLE spectra at the free exciton energy depend on the monitoring PL peak, the kind of crystals, and temperatures. A proposed relaxation process of excited electron-hole pairs explains peak and dip structures of PLE spectra at the free exciton energies.