Giant magnetoresistance in a two-dimensional electron gas modulated by periodically repeated magnetic barriers

摘要

The giant magnetoresistance effect is investigated in a two-dimensional electron gas modulated by periodically repeated magnetic barriers, which can be realized by depositing parallel ferromagnets on the top and the bottom of a heterostructure. It is found that the magnetoresistance ratio (MRR) of the present system shows a strong dependence on the number of ferromagnetic unit cells. The modified MRR (MMRR) shows oscillations, where the number of peaks is determined by the number of units, and our study indicates that for experimentally accessible parameters for a GaAs heterostructure the value of the MMRR can be as high as 55 for a realistic electron density.