Efficient thermo-spin conversion in van der Waals ferromagnet FeGaTe

Abstract

Recent discovery of 2D van der Waals (vdW) magnetic materials has spurred progress in developing advanced spintronic devices. A central challenge lies in enhancing the spin-conversion efficiency for building spin-logic or spin-memory devices. We systematically investigated the anomalous Hall effect and anomalous Nernst effect in above-room-temperature van der Waals ferromagnet FeGaTe with perpendicular anisotropy, uncovering significant spin-conversion effects. The anomalous Hall effect demonstrated an efficient electric spin-charge conversion, with a notable spin Hall angle of 6 $\%$ - 10.38 $\%$. The temperature-dependent behavior of the anomalous Nernst voltage primarily results from the thermo-spin conversion. Uniquely, we have experimentally achieved thermo-spin polarization values of over 690 $\%$ at room temperature and extremely large of 4690 $\%$ at about 93 K. This study illuminates the potential of vdW ferromagnets in advancing efficient spin conversion devices.