Thickness-dependent SOT effective fields and magnetization control in Topological insulator/2D-ferromagnet Bi2Te3/Cr1+δTe2 Van der Waals heterostructures with PMA

Second harmonic Spin-Orbit Torques (SOT) evaluation has been used to quantify amplitudes of Field-like (FL) and Damping-like (DL) in Bi
2
Te
3
/Cr
1+δ
Te
2
Van der Waals (VdH) heterostructures grown by Molecular Beam Epitaxy (MBE). Although the FL effective field was found to be larger than the DL component, as expected for interfacial mechanisms for SOT generation, the FL/DL torque-ratio exhibits a non-monotonic dependency on the thickness of the ferromagnet layer. At 10 repetitions of the CrTe
2
VdH trilayer, the ratio displays its maximum value with the FL field being about 100 times larger than DL field. The amplitudes of DL field are on par with values for Spin-Hall materials. We also report current-induced magnetization reversal in Bi
2
Te
3
/Cr
1+δ
Te
2
with perpendicular magnetic anisotropy (PMA).