Thermospin effects in a T-shaped spin valves with spin-flip scattering

Abstract

With the help of the nonequilibrium Green's function technique, we theoretically analyze the thermospin property through a typical T-shaped spin valve with spin-flip scattering in the linear regime. The influences of spin-flip coefficient of interdot λ, spin-flip coefficient of intradot η and interdot hopping coefficient t+δσΔt on thermospin property are discussed. As interdot hopping coefficient t is equal to energy level ε, the spectrum of Gs shows Fano-like effect with ε variation. Antiresonance position of Gs is almost unchanged and its width becomes narrower with ε increasing. Spin thermopower Ss is close to the maximum of the peak and charge thermopower Sc is equal to zero for t=ε. As a result, the pure spin thermopower Ss can be obtained, which means that a pure spin current may be produced by a temperature gradient in our system. It is found that spin figure of merit ZTs can reach a considerable value by adjusting key parameters of the system, such as Δt, β, α, ϕ. The typical T-shaped spin valve can be treated as a stable thermospin battery which allows to convert the heat energy to spin voltage, thus produces the pure spin current in the device.