Electron spin resonance study of CuGa1-xMnxSe2 magnetic semiconducting compounds

We report on the magnetic properties of the diluted magnetic semiconductor CuGa1-xMnxSe2. For this, Electron spin resonance (ESR) experiments in the temperature range 70 K < T < 300 K, were performed. The samples were synthesized by direct fusion of stoichiometric mixtures of the elements, with Mn composition from x = 0.0 to 0.25. The ESR integral intensity, resonance field, and linewidth, have been measured as functions of temperature and Mn concentration. We identify a paramagnetic phase above a critical temperature of the order of 250-260 K. Below this temperature, the spin system reorders into certain magnetic phase not well identified. The inclusion of Mn induces local fields that increase the resonance field, with resulting g-values less than 2.0. The behavior of the ESR linewidth is similar to that observed in II-Mn-VI alloys, and can be described by the modified Huber equation. (c) 2012 Elsevier B.V. All rights reserved.