Long-lived two-domain spin structures in a non-degenerate gas

We demonstrate that linear differential potentials give rise to long-lived longitudinal spin domains with decoupled transverse and longitudinal spin dynamics. At ultra-cold temperatures, coherent spin-rotating interactions lengthen the diffusion time of spin domains in non-degenerate gases. The spin dynamics are further altered by applying linear differential potentials of varying gradients. At specific gradients, we observe stable spin domains for a range of densities and temperature. In the hydrodynamic limit, the measured optimal gradients agree well with a quantum Boltzmann theory.