The critical role of next-nearest-neighbor interlayer interaction in the magnetic behavior of magnetic/non-magnetic multilayers

Abstract

A striking multiple-step behavior has been observed in magneto-resistance measurements during magnetization reversal in anti-ferromagnetically coupled GaMnAs/GaAs: Be multilayers. This behavior arises from the splitting of the energy degeneracy of spin configurations established by nearest-neighbor interlayer exchange coupling (NN IEC) with contribution from the next-nearest-neighbor (NNN) IEC. This observation reveals that NNN IEC plays a crucial role in the magnetic behavior of these multilayer structures.