Spin-polarized electron transport through a non-magnetic double barrier semiconductor heterostructure

The spin-polarized electron resonant tunneling at zero magnetic field through a double barrier hetero structure of non-magnetic III-V semiconductor is theoretically investigated within the envelop function approximation and the Kane model for the bulk. An elegant model is proposed to study the combined effects of Dresselhaus and in-plane Rashba spin-orbit interactions on the spin-dependent tunneling through double barriers of strained hetero structures. Enhanced degree of spin-polarization and easily tunable wider range of energy for a specific polarization are predicted. We estimate that the polarization can reach cent percent with moderate applied electric field. Our investigations show that spin-relaxation can be suppressed by compensating the bulk and structural inversion symmetries using appropriate electric potential. This effect could be engineered in the fabrication of spin-dependent optoelectronic devices.