INCOMMENSURATE ANTIFERROMAGNETIC ORDER IN STRAINED LAYER MNSE/ZNTE SUPERLATTICES

Neutron diffraction data from MnSe/ZnTe, a MBE-grown superlattice system containing zinc-blende (ZB) MnSe layers subjected to a considerable tensile stress, indicate the formation of an incommensurate helical AF structure which is clearly different from the Type III FCC AF order seen in unstrained ZB Mn chalcogenides, and in MnSe/ZnSe and MnTe/ZnTe superlattices with compressive strain. Energy considerations show that such an arrangement results from strain-induced anisotropy in the nearest-neighbor exchange.