Fig. 3: Angle-dependent harmonic Hall measurements in TaIrTe4/Fe3GaTe2 heterostructure.
From: Tunable unconventional spin orbit torque magnetization dynamics in van der Waals heterostructures
a Schematic of the TaIrTe4/Fe3GaTe2 heterostructure, illustrating the effects of damping-like torques (\({{{{\boldsymbol{\tau }}}}}_{{{{\bf{DL}}}}}^{{{{\bf{XY}}}}}\) and \({{{{\boldsymbol{\tau }}}}}_{{{{\bf{DL}}}}}^{{{{\bf{Z}}}}}\)) and field-like torques (\({{{{\boldsymbol{\tau }}}}}_{{{{\bf{FL}}}}}\)) on Fe₃GaTe₂ magnetization when the current is applied along the a-axis of TaIrTe₄ layer19. The 2nd harmonics Hall voltage (\({V}_{{xy}}^{2\omega }\)) measurement scheme is shown with an external in-plane magnetic field at angle ΦB relative to the a.c. current direction Iac. b \({V}_{{xy}}^{2\omega }\) vs ΦB of Dev1 at magnetic field 7 T and temperature 300 K. The solid lines are fitted with Eqs. 1 and 2. The second panel shows \({V}_{{xy}}^{2\omega }\) vs ΦB for varied magnetic fields (7-12 T). c–e Coefficient \({{V}_{{xy}}^{2\omega }}_{\cos {\varPhi }_{B}}\)(\(\cos {\varPhi }_{B}\) dependent in \({V}_{{xy}}^{2\omega }\)), \({{V}_{{xy}}^{2\omega }}_{\sin {\varPhi }_{B}}\)(\(\sin {\varPhi }_{B}\) dependent in \({V}_{{xy}}^{2\omega }\)) and \({{V}_{{xy}}^{2\omega }}_{\cos 2{\varPhi }_{B}}\)(\(\cos {2{\phi }}_{B}\) dependent in Vxy2ω) as a function of 1/(H-Hk) and 1/H under different current densities Ja.c.. The error bar in c, d and e are obtained from fitting of experimental data in (b) using Eq. 1. f Angle sweep of \({V}_{{xy}}^{2\omega }\) at different temperatures (2–325 K) at a constant magnetic field of 10 T. Solid lines are fit to experimental data using Eq. 1. g Damping-like field components (\({H}_{{DL}}^{X},{{H}_{{DL}}^{Y},H}_{{DL}}^{Z}\)) as a function of current density, with linear fits estimating HDL/ Ja.c., whereas error are obtained from the linear fit of c, d and e data. h Temperature dependence of HDL/ Ja.c. for TaIrTe4/Fe3GaTe2 device. Insets show the energy dispersion curve of type-II Weyl semimetal and tuning of Fermi level energy (EF) with temperature. The error bars in (h) are obtained by fitting experimental data in (f) using Eq. 1.
