Direct Tunneling and Related TMR Anomalies in Magnetic Tunnel Junctions With Embedded Nanoparticles

This article shows simulations of the electron direct tunneling through the MgO insulating layer in the magnetic tunnel junction with embedded non-magnetic and magnetic nanoparticles (NPs). The approach of weak magnetic NPs is considered at low temperature, where the related values of the electron wavenumbers, as well as exchange energy in NPs, are a few times smaller than in the bulk. The results show the opportunities for the significant enhancement of the tunnel magnetoresistance (TMR) with voltage. The theory predicts and explains some anomalous periodicity of TMR with voltage including the stable plateau at some conditions.