Motivated by recent experiments measuring the spin transport in ultracold
unitary atomic Fermi gases (Sommer et al., 2011; Sommer et al., 2011), we
explore the theory of spin and heat transport in a three-dimensional
spin-polarized atomic Fermi gas. We develop estimates of spin and thermal
diffusivities and discuss magnetocaloric effects, namely the the spin Seebeck
and spin Peltier effects. We estimate these transport coefficients using a
Boltzmann kinetic equation in the classical regime and present experimentally
accessible signatures of the spin Seebeck effect. We study an exactly solvable
model that illustrates the role of momentum-dependent scattering in the
magnetocaloric effects.Comment: 18 pages, 6 figures, slight notation changes from previous versio
