Abstract
This paper investigates how an applied magnetic field, the quantum size, and spin polarization effect an asymmetric heterostructure composed of InAs, GaAs, and GaSb semiconductors. Using a theoretical approach based on the transfer matrix method and taking into account the Rashba and Dresselhaus spin-orbit interactions, we calculate the spin-dependent transmissions of spin-up and -down electrons and their spin polarization across our heterostructure. Our results indicate that the transmission coefficients and the resonance states can be tuned to a red or blue shift by adjusting the quantum wells and the barrier widths. Two resonance states are detected when the width of the central barrier Lbc is reduced. Furthermore, we show that the impact of an applied magnetic field on the spin polarization can polarize 100% of either spin -up or -down electrons by selecting the appropriate range of incident energy and suitable magnetic field. These results are useful for the design and fabrications of spin-filter devices operating under an applied magnetic field.