Effect of Γ–X Band Crossover on Resonant Tunneling Properties in GaAs/Ga0.7Al0.3As with Dresselhaus Spin-Orbit Interaction

Our theoretical study focused on the spin-dependent electron transport characteristics in GaAs/Ga0.7Al0.3As resonant tunnel barriers. This system exhibits spin-splitting, which is a consequence of the Dresselhaus spin-orbit interaction. Calculation of the transmission coefficient and spin-polarization efficiency relies on the matrix method. The pressure influences the barrier transparency and degree of polarization. The maximum of 72% spin-polarization is achieved in this work at critical pressure. The role of the Γ–X band crossover is accounted for in this theory. The spin-polarization increases without the Γ–X band crossover and the same decreases with the Γ–X band crossover. At the critical pressure, the degree of spin polarization is high. Analysis of the electron dwell time reveals that spin-down electrons spend more time in the system than spin-up electrons. We also found that the dwell time reaches its maximum when the heterostructure is subjected to the critical pressure.