Ballistic transport in extended Datta–Das spin field effect transistors

The model of the Datta–Das spin field effect transistor [S. Datta, B. Das, Appl. Phys. Lett. 56 (1990) 665] is extended in several respects: (1) the Rashba effect and Dresselhaus effect coexist; (2) the incoming and outgoing leads are both ferromagnetic; (3) the interfacial scattering and band mismatch are taken into account. By using the Griffith boundary conditions, the transmission coefficients and, thus, the Landauer–Büttiker conductance are obtained analytically. The transmission probability and conductance of the spin field effect transistor are studied in detail.