We demonstrate the introduction of high carrier densities into two and
three-dimensional magnetic semiconductor heterostructures that contai
n large local concentrations of magnetic moments. The use of (ZnSe)(m-
f)(MnSe)(f) digital alloys readily allows the fabrication of epilayer
samples of moderate Mn composition with carrier concentrations up to s
imilar to 10(19) cm(-3). Modulation doping of ZnSe/Zn1-x-yCdyMnxSe qua
ntum wells enables the fabrication of a 2-D electron gas confined with
in the magnetic region with sheet concentrations up to similar to 6 x
10(11) cm(-2). (C) 1996 American Institute of Physics.