Time-resolved quantum spin transport through an Aharonov–Casher ring

Abstract

After obtaining an exact analytical time-varying solution for the Aharonov-Casher conducting ring embedded in a textured static/dynamic electric field, we investigate the spin-resolved quantum transport in the structure. It is shown that the interference patterns are governed by not only the Aharonov-Casher geometry phase but also the instantaneous phase difference of spin precession through different traveling paths. This dynamic phase is determined by the strength of the applied electric field and can have substantial effects on the charge/spin conductances, especially in the weak field regime as the period of spin precession comparable to that of the orbital motion. Our studies suggest that a low-frequency normal electric field with moderate strength possesses more degrees of freedom for manipulating the spin interference of incident electrons.

Isotropic All-electric Spin analyzer based on a quantum ring with spin-orbit coupling

“…Quantum interference between the two arms of the ring provides suitable means for controlling the spin in the nano-scale, which has been proven by the Green's function method [18,25] or Griffith's boundary conditions [15, 19-21, 23, 24, 26]. The first order linear approximation with full transparent contacts was also reported [11,14,16,27], albeit without the backscattering effect. The S-matrix method [28,29] presents a rough assessment of the backscattering by fixing the energydependent coupling parameter between the leads and ring as constant.…”