Efficient Spin-Orbit Torque Switching of the Semiconducting Van Der Waals Ferromagnet Cr2 Ge2 Te6.

Being able to electrically manipulate the magnetic properties in recently discovered van der Waals ferromagnets is essential for their integration in future spintronics devices. Here, the magnetization of a semiconducting 2D ferromagnet, i.e., Cr2 Ge2 Te6 , is studied using the anomalous Hall effect in Cr2 Ge2 Te6 /tantalum heterostructures. The thinner the flakes, hysteresis and remanence in the magnetization loop with out-of-plane magnetic fields become more prominent. In order to manipulate the magnetization in such thin flakes, a combination of an in-plane magnetic field and a charge current flowing through Ta-a heavy metal exhibiting giant spin Hall effect-is used. In the presence of in-plane fields of 20 mT, charge current densities as low as 5 × 105 A cm-2 are sufficient to switch the out-of-plane magnetization of Cr2 Ge2 Te6 . This finding highlights that current densities required for spin-orbit torque switching of Cr2 Ge2 Te6 are about two orders of magnitude lower than those required for switching nonlayered metallic ferromagnets such as CoFeB. The results presented here show the potential of 2D ferromagnets for low-power memory and logic applications.