Spin-polarized transmission across heterostructure based on an InAs/GaSb/InGaAs system: Effect of accelerating quantum wells

Abstract

Electronic transmission and spin polarization have been computed as a function of the incident electron energy for heterostructures like InAs/GaSb/InGaAs triple barriers. This was achieved using the transfer matrix method while taking into account the Rashba spin-orbit interaction. The desired spin polarization can be adjusted through two InGaAs accelerating quantum wells. The spin-up and down transmission coefficients and the spin polarization can be tuned by varying the depths and widths of the accelerating quantum wells, as well as the incident wave vector k//. When we increase the in-plane wave vector, the spin polarization increases, and the transmission peaks shift towards higher energies. However, when we increase the depth of the wells, the transmission peaks shift towards lower energies, and the spin polarization reaches 32%. These interesting results could be employed in the design and fabrication of spin filters by selecting the appropriate accelerating quantum wells.