Doping profile vs spin-resolved subband structure and spontaneous magnetization of selectively Mn-doped DMS narrow quantum wells

The interrelation between magnetic properties and doping profile of selectively Mn-doped (p-AlGaAs)/(GaAs, Mn)/(p-AlGaAs) quantum wells (QWs) is studied by analyzing the self-consistent spin-resolved subband structures of the system. The effective potentials felt by the majority and minority spin carriers in the QW depend markedly on the doping profiles of the Mn ions and impurities in the barriers. Various doping profiles of the magnetic ions are considered to vary the overlap of the carriers and magnetic ions in the QW, and the resulting spin-resolved carrier distribution, subband structure, and ferromagnetic tendency of the system are examined. Our result shows that (1) Curie temperature depends sensitively on the width and location of Mn doping inside the QW for a given 2D density of Mn ions and (2) modulation doping of acceptors in the barriers does not necessarily enhance the T-c of a given Mn-doped narrow QW structure. (c) 2006 Elsevier B.V. All rights reserved.