Characterization of room-temperature in-plane magnetization in thin flakes of CrTe2 with a single-spin magnetometer

Abstract

We demonstrate room-temperature ferromagnetism with in-plane magnetic anisotropy in thin flakes of the $\mathrm{Cr}{\mathrm{Te}}_{2}$ van der Waals ferromagnet. Using quantitative magnetic imaging with a single-spin magnetometer based on a nitrogen-vacancy defect in diamond, we infer a room-temperature in-plane magnetization in the range of $M\ensuremath{\sim}27$ kA/m for flakes with thicknesses down to 20 nm. In addition, our measurements indicate that the orientation of the magnetization is not determined solely by shape anisotropy in micron-sized $\mathrm{Cr}{\mathrm{Te}}_{2}$ flakes, which suggests the existence of a non-negligible magnetocrystalline anisotropy. These results make $\mathrm{Cr}{\mathrm{Te}}_{2}$ a unique system in the growing family of van der Waals ferromagnets, as it is the only material platform known to date that offers an intrinsic in-plane magnetization and a Curie temperature above 300 K in thin flakes.