Magnetic-electric controllable spin transport in semiconductors superlattic
半导体超晶格系统中的磁电调控电子自旋输运研究

By solving electron tunneling problem in semiconductor superlattice, the magnetic-electric controllable spin transport is theoretically investigated.The results show that, with magnetic modulation only,the spin transmission will separate, and with the magnetic filed increasing,the conductance polarization is enhanced and its peaks are widened. By both magnetic and single interval electric barrier modulation,the conductance polarization will be evidently improved; and at the same time,there are two distinct transport regions for different electric modulation, in which the down-spin electron obeys different change rules with different electric filed.However,applying electric modulation at intervals of two periods on the magnetic superlattic,it is noticed that the critical behavior of electron spin transport disappears,and the resonant peak of the conductance polarization also degenerates in the high energy region.These results show that the symmetry is an important factor for spin transport in the semiconductor superlattice.