Spin current generation due to differential rotation

We study nonequilibrium spin dynamics in differentially rotating systems, deriving an effective Hamiltonian for conduction electrons in the comoving frame. In contrast to conventional spin current generation mechanisms that require vorticity, our theory describes spins and spin currents arising from differentially rotating systems regardless of vorticity. We demonstrate the generation of spin currents in differentially rotating systems, such as liquid metals with Taylor-Couette flow. Our alternative mechanism will be important in the development of nanomechanical spin devices.