Lifetime shortening from micro to nano in copper doped CaS at liquid nitrogen temperature

Abstract

Copper doped Calcium sulphide phosphors having variable concentrations of killer impurities Fe, Co and Ni have been synthesized and then using laser excitation of samples for there photoluminescence behaviour, their decay-curve analysis has been done. Various strong emissions in these phosphors have been detected and the corresponding excited state lifetimes are measured at liquid nitrogen temperature. Studies have also been carried out to see the effect of killer impurities on the phosphorescence excited-state life times. With the addition of killer impurities appreciable decrease in lifetime values (microsecond to nanosecond) is reported. These studies are quite useful and find applications in the areas like optical memories, sensors, luminescent screens, laser-beam detection and alignment, colour displays, printing, etc. This work is a extension of the work earlier done by Bhatti. etal(14-16) on CaS phosphors. © 2021 Elsevier B.V., All rights reserved.