Generation of spin currents by a temperature gradient in a two-terminal device

Theoretical and experimental studies of the interaction between spins and temperature are vital for the development of spin caloritronics, as they dictate the design of future devices. In this work, we propose a two-terminal cold-atom simulator to study that interaction. The proposed quantum simulator consists of strongly interacting atoms that occupy two temperature reservoirs connected by a one-dimensional link. First, we argue that the dynamics in the link can be described using an inhomogeneous Heisenberg spin chain whose couplings are defined by the local temperature. Second, we show the existence of a spin current in a system with a temperature difference by studying the dynamics that follows the spin-flip of an atom in the link. A temperature gradient accelerates the impurity in one direction more than in the other, leading to an overall spin current similar to the spin Seebeck effect. Spin caloritronics exploits the effect of temperature on spin currents with a focus on features such as spin dependent thermal conductance, which are ideally suited for next generation spintronic devices. Here, the authors theoretically investigate a cold atom simulator of spin caloritronics comprising a one-dimensional spin chain between two temperature reservoirs and consider the dynamics of a spin impurity (spin flip) introduced into the chain.