Magnetothermal transport in the spin-$\frac{1}{2}$ easy-axis antiferromagnetic chain

By an exact analytical approach we study the magnetothermal transport in the spin-$\frac{1}{2}$ easy-axis Heisenberg model, in particular the thermal conductivity and spin Seebeck effect as a function of anisotropy, magnetic field, and temperature. We stress a distinction between the common spin Seebeck effect with fixed boundary conditions and the one (intrinsic) with open boundary conditions. In the open boundary spin Seebeck effect we find exceptional features at the critical fields between the low field antiferromagnetic phase, the gapless one, and the ferromagnetic at high fields. We further study the development of these features as a function of easy-axis anisotropy and temperature. We point out the potential of these results to experimental studies in spin chain compounds—candidates for spin current generation in the field of spintronics.