Mechanism of radiative Mn2+ intra-shell recombination in bulk ZnMnS

Origin of a fast component of the photoluminescence decay of Mn2+ intra-she ll T-4(1) --> (6)A(1) transition is discussed based on the results of photo luminescence, photoluminescence kinetics and optically detected magnetic re sonance experiments performed for bulk ZnMnS samples with about 1% Mn fract ion. It is demonstrated that a fast component of the photoluminescence deca y, reported previously for quantum dot structure and related to quantum con finement effects, is also observed in bulk samples and is related by us to very efficient spin cross-relaxation effects.