Influence of local magnetization on acceptor-bound complex state in Hg_1-xMn_xTe single crystals

We performed temperature-dependent magnetic measurements and infrared photoluminescence (PL) measurements in various geometries on a series of p-type Hg_1-xMn_xTe single crystals (0.20 ≤ x ≤ 0.26). Evolution of PL features was observed, and zero-field spin splitting was identified for the acceptor-bound magnetic polaron (A⁰BMP). The results show direct evidence for local spontaneous magnetization of the A⁰BMP. Comparison with the Ditel-Spałek model indicates that besides the fluctuation and collective regimes, the A⁰BMP exhibits a new regime at low temperatures owing to the formation of the spin-glass state in Hg_1-xMn_xTe. The dissociation energy of the exciton bound to the A⁰BMP ((A⁰,X)BMP) varied rapidly with temperature, and the ratio of the dissociation energy of the (A⁰,X)BMP to the binding energy of the A⁰BMP was larger than the classical value of the A⁰X and no longer a constant, which breaks the Haynes rule. The free exciton localization process helps enhance the local magnetization of the (A⁰,X)BMP by transferring energy from the carrier system to the Mn-spin system, and it may lead to a photoinduced configuration of non-interacting ferromagnetic domains or the photoinduced magnetization effect.