Thermal-spin injection in a quantum dot coupled to electrodes with a weak induced spin disproportion

Abstract In this work, we theoretically propose a thermal-spin injector, which is constructed by embedding a semiconductor quantum dot between two nonmagnetic electrodes. Analogous to the nonmagnetic graphene quantum wires reported in reference [ Nat. Nanotech. 13, 107], a small chemical potential difference exists between the two spin channels in the electrodes. Our numerical simulations reveal that, even in the absence of a spin bias voltage across the electrodes, the system is capable of generating spin-polarized thermoelectric currents driven by temperature gradients, as well as producing pure spin currents.Moreover, both the charge current and the spin current can be precisely controlled by either the gate voltage applied to the quantum dot or the temperature gradient between the electrodes. We believe that these results can be experimentally verified in the field of spintronics, thereby providing a new strategy for the generation and manipulation of spin currents.