Influence of Paired Mn²⁺ Centers on the Luminescence Spectra of CaS:Mn²⁺

Abstract

The photoluminescence decay of the CaS:Mn 2+ phosphor activated with a fairly large amount of Mn 2+ (1-2mol%) consists of slow (8.5 ms at 80 K) and fast (550 µs at 80 K) exponential decay components due to the single and paired Mn 2+ centers, respectively. From the measurements of time-resolved emission spectra, the emission bands due to the single and paired Mn 2+ centers were found to be located at 590 and 599 nm, respectively, at 80 K. Five bands in the time-resolved excitation spectrum of the paired Mn 2+ center are observed on the slightly low-energy side relative to those of the single Mn 2+ center. The time-resolved excitation spectra were also investigated for SrS:Mn 2+ phosphor.