Spin Nernst magnetoresistance for magnetization study of FePS3

The magnetization of the antiferromagnetic van der Waals material ${\mathrm{FePS}}_{3}$ is investigated via the spin Nernst magnetoresisance (SNMR) and spin Seebeck effect (SSE). A heater and Pt detector strips are fabricated on top of a ${\mathrm{FePS}}_{3}$ flake which generates a temperature gradient in ${\mathrm{FePS}}_{3}$ and in the Pt detector strips. We are able to detect the SNMR in Pt, which is an interface effect, and detect the SSE response, which is a bulk effect. We conclude that there are uncompensated magnetic moments in ${\mathrm{FePS}}_{3}$ at the interface with Pt. Via the SNMR we are able to extract the real and imaginary parts of the spin mixing conductance assuming a fully uncompensated top layer. For an in-plane thermal conductivity of 10 W/($\mathrm{m}\phantom{\rule{0.16em}{0ex}}\mathrm{K}$) and therefore a temperature gradient of 6000 K/m in Pt we find that ${G}_{r}=1.9\ifmmode\pm\else\textpm\fi{}0.06\ifmmode\times\else\texttimes\fi{}{10}^{13}\phantom{\rule{0.28em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\text{m}}^{\ensuremath{-}1}$ and ${G}_{i}=4.8\ifmmode\pm\else\textpm\fi{}0.02\ifmmode\times\else\texttimes\fi{}{10}^{11}\phantom{\rule{0.28em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\text{m}}^{\ensuremath{-}1}$. In addition, the temperature gradient in ${\mathrm{FePS}}_{3}$ generates a magnon current in ${\mathrm{FePS}}_{3}$ via the SSE which can be detected by the Pt detector strips. We are able to extract a magnon diffusion length of $1.3\ifmmode\pm\else\textpm\fi{}0.5$ and $0.5\ifmmode\pm\else\textpm\fi{}0.1\phantom{\rule{0.28em}{0ex}}\textmu{}\mathrm{m}$ for thermally generated magnons in ${\mathrm{FePS}}_{3}$ for 40 and 20 nm thicknesses, respectively.