Generation of spin currents by a temperature gradient in strongly interacting one-dimensional systems

We argue that the finite-temperature dynamics of a strongly interacting one-dimensional system can be modeled using a Heisenberg spin chain whose couplings are defined by the local temperature [see arXiv:2101.02020]. This allows us to introduce a microscopic theory in which spin currents are generated by a temperature gradient. We demonstrate the generation of a spin current due to the temperature gradient by studying the dynamics that follows a spin-flip of an atom in the chain. A temperature gradient accelerates the atom in one direction more than in the other, leading to an overall spin current, which is similar to the spin Seebeck effect.