Temperature dependence of the relaxation decay time and the integrated intensity of the photoluminescence from the magnetic semiconductor CdCr2Se4

The photoluminescence relaxation decay time of the band-to-band transition in CdCr2Se4was measured from 4 to 250 K. The decay time was measured to be ∼ 45 ps at 4 K, which monotonically decreased to < 10 ps at 250 K. The integrated intensity of the steady-state photoluminescence from CdCr2Se4was measured from 15 to 220 K. The steady-state intensity increased as the temperature decreased, and increased quadratically with the excitation intensity. The temperature dependence of the relaxation decay time is theoretically fitted to the temperature dependence of the steady-state integrated intensity.