Thermoelectric properties of a quantum dot coupled to magnetic leads by Rashba spin-orbit interaction

Abstract

We consider a single-level quantum dot coupled to two leads which are ferromagnetic in general. Apart from tunneling processes conserving electron spin, we also include processes associated with spin-flip of tunneling electrons, which appear due to Rashba spin-orbit coupling. Charge and heat currents are calculated within the non-equilibrium Green's function technique. When the electrodes are half-metallic (fully spin polarized), the Rashba spin-orbit coupling leads to Fano-like interference effects, which result in an enhanced thermoelectric response. It is also shown that such a system can operate as efficient heat engine. Furthermore, the interplay of Rashba spin-orbit coupling and Zeeman splitting due to an external magnetic field is shown to allow control over such parameters of the heat engine as the power and efficiency.

Quantum thermodynamic devices: from theoretical proposals to experimental reality

“…The theoretical proposal by Bergenfeldt et al 245 has had significant impact. In particular, the hybrid engine found attention in work on thermoelectrics with quantum dots [260][261][262][263][264][265][266][267][268][269] and other quantum heat engine designs [270][271][272][273][274] .…”

Photon-Mediated Thermoelectric and Heat Currents through a Resonant Quantum Wire-Cavity System

“…The role of spin, including Zeeman spin [20] and spin-orbit coupling such as the Rashba effect [21], in thermal transport has been of interest for investigating thermospin current in non-conventional spintronic devices. It is shown that the Rashba spin-orbit coupling forms Fano-like interference effects, which result in an enhanced thermoelectric response [22]. Tuning the Rashba coefficient, anti-crossings in the energy spectrum have been observed leading to the Aharonov-Casher destructive phase interference in the quantum ring system [23,24].…”