Suppression of Mn photoluminescence in ferromagnetic state of Mn-doped ZnS nanocrystals

Abstract

Magnetic ordering can tune optical properties of photoluminescent dilute magnetic semiconductors. The results of a magnetic field dependent photoluminescence (PL) up to 50 T above and below ferromagnetic transition temperature ${T}_{C}$ in Mn-doped ZnS nanocrystals have been reported here. The PL intensity corresponding to internal transition between states of Mn significantly decreases with application of magnetic field below ${T}_{C}$ but no such suppression was observed above ${T}_{C}$ even at 50 T. The zero-field PL intensity also exhibits continuous suppression with decreasing temperature in the ferromagnetic state. The PL intensity profiles could be fitted consistently using a model of magnetic-ordering-induced spin-sensitive energy transfer to Mn states below ${T}_{C}$.