DOI: 10.5061/dryad.s7h44j1dh
title: Data from: Field-free deterministic switching of all-van der Waals spin-orbit torque system above room temperature

description: Two-dimensional van der Waals (vdW) magnetic materials hold promise for
 the development of high-density, energy-efficient spintronic devices for
 memory and computation. Recent breakthroughs in material discoveries and
 spin-orbit torque (SOT) control of vdW ferromagnets have opened a path for
 integration of vdW magnets in commercial spintronic devices. However, a
 solution for field-free electric control of perpendicular magnetic
 anisotropy (PMA) vdW magnets at room temperatures, essential for building
 compact and thermally stable spintronic devices, is still missing. Here,
 we report a solution for the field-free, deterministic and non-volatile
 switching of a PMA vdW ferromagnet, Fe3GaTe2 above room temperature (up to
 320 K). We use the unconventional out-of-plane anti-damping torque from an
 adjacent WTe2 layer to enable such switching with a low current density of
 2.23 × 106 A cm-2. This study exemplifies the efficacy of low-symmetry vdW
 materials for spin-orbit torque control of vdW ferromagnets and provides
 an all-vdW solution for the next generation of scalable and
 energy-efficient spintronic devices.
description: Device Morphology Thicknesses of the
 constituent flakes were characterized after encapsulation using a Cypher
 VRS AFM. Polarized Raman spectra of WTe<sub>2</sub> flakes was
 acquired using a 532 nm laser with a WITec Alpha300 Apyron Confocal Raman
 microscope, by rotating the polarizer and analyzer while the sample was
 static. Transport Measurements All
 transport measurements were performed in a 9 T PPMS DynaCool system.
 Measurements were performed by sourcing current using a Keithley 6221
 current source and measuring the transverse voltage across the devices,
 using a Keithley 2182A nanovoltmeter. Anomalous Hall effect measurements
 with field sweeps were performed using a drive current of 50 – 200 A. For
 the current-induced switching measurements, a 1 ms pulse of write-current
 was followed by 999 ms of read pulses ( 200 A). Field could be applied in
 and out of the sample plane using the PPMS’ horizontal rotator
 module. First Principles Calculations
 Electronic properties calculation and structural optimizations
 were performed using density functional theory (DFT) with the Quantum
 ESPRESSO package. We use the optimized norm-conserving Vanderbilt (ONCV)
 pseudopotentials with Perdew-Burke-Ernzerhof (PBE) functionals to account
 for the exchange-correlation interaction. To accurately describe the
 structural properties of layered FGaT structure, we use the nonlocal
 vdW-DF2 functional for the van der Waals interaction. A large plane wave
 cut-off energy of 60 Ry (~ 816 eV) is used for all calculations. The FGaT
 monolayer and bilayer are modeled by the slab supercells, with the
 separations between the neighboring slabs being about 20 Å. A 16×16×1
 k-point mesh is used for monolayer and bilayer FGaT, while 14×14×2 mesh is
 used for the bulk FGaT. These parameters are selected based on the
 convergence test of the total energy. The atomic positions and lattice
 constants are optimized by the BFGS quasi-newton algorithm, in which the
 convergence values for the forces and stress components are 0.0001
 Ry/a.u.<sup>3</sup> and 0.005 GPa, respectively. To determine
 the magnetic anisotropy energy (MAE) of FGaT, we first perform the total
 energy calculations for an in-plane magnetization (along the x-axis) and
 then out-of-plane magnetization (along the z-axis), including spin-orbit
 coupling (SOC). Then, the MAE is given by the difference in total energy
 for the two systems.
description: # Field-free deterministic switching of all-van der Waals spin-orbit
 torque system above room temperature
 Raw data used in
 generating all the plots in the manuscript (main text and supplementary)
 is provided here in spreadsheet format. One file is created for every
 composite figure, and the data from constituent sub-figures is added to
 separate pages of the file. For the DFT calculations using Quantum
 Espresso, input files, output files and output data are attached
 separately as a zipped file. A separate README file is provided in the
 zipped file which describes organisation of the DFT codes and results.
 Below we provide detailed description of the data (abbreviations, data
 arrangement) for all the figures. **Fig. 1** **(D)** Raman spectroscopy
 data for the device D1. First column is the Raman shift, while subsequent
 columns give the Raman intensity for different angles, Phi (0, 3, 6, ...,
 357, 360 degree) **Fig. 2** **(A)** Anomalous Hall effect data for device
 D1, at different temperatures (260, 280, 300, 320, 330, 340K). For each
 temperature, 4 columns of data are provided - backward field (H), backward
 Hall resistance (Rxy), forward field (H) and forward Hall resistance
 (Rxy), respectively. **(B)** Anomalous Hall effect data for device D1, at
 different temperatures (10, 50, 100, 150, 200K). For each temperature, 4
 columns of data are provided - backward field (H), backward Hall
 resistance (Rxy), forward field (H) and forward Hall resistance (Rxy),
 respectively. **(C)** Variation of anomalous Hall resistance (RxyAHE) and
 coercivity in the device D1 for varying temperatures (T). These values are
 derived from the curves in Fig. 2A and 2B. **(D)** Anomalous Hall
 resistance for device D1, for field swept in the plane of the device. Four
 columns of data are provided - backward field (H), backward Hall
 resistance (Rxy), forward field (H) and forward Hall resistance (Rxy),
 respectively. **Fig. 3** **(B)** Anomalous Hall resistance of device D2
 (resistance vs current) for the 4 cases - current pulses swept from (0 to
 -4.5 mA  to 0) or (0 to 4.5 mA to 0 mA), for the device initialized at m
 =1 and m = -1. **(C)** Current induced switching in device D2 (resistance
 vs current) for the two cases - negative and positive external field.
 **(D)** Time series of Hall resistance measurement - time and resistance.
 **Fig. 4** **(A)** Switching data, for different temperatures (300, 305,
 ..., 330K). For each temperature, there are five columns - current (I) and
 four resistance (R). Plotted data shows the mean and standard deviation of
 the four resistances at that temperature. **(C)** Switched resistance
 (RxyAHE) for different temperatures (T). The data points are derived from
 the curves in figure 4A. **(D)** Time series of Hall resistance
 measurement - time and resistance. Two pieces, each 50 second long, are
 provided. **SuppFig. 1** **(C)** Atomic force microscopy (AFM) line
 profile - x-coordinate and height. **SuppFig. 2** **(B)** Raman
 spectroscopy data for the device D2. First column is the Raman shift,
 while subsequent columns give the Raman intensity for different angles,
 Phi (0, 6, 12, ..., 354, 360 degree). **(E)** Atomic force microscopy
 (AFM) line profile - x-coordinate and height. **(G)** Atomic force
 microscopy (AFM) line profile - x-coordinate and height. **SuppFig. 3**
 **(A)** Anomalous Hall effect data for device D2, at different
 temperatures (260, 280, 300, 320, 340K). For each temperature, 4 columns
 of data are provided - backward field (H), backward Hall resistance (Rxy),
 forward field (H) and forward Hall resistance (Rxy), respectively.\
 **(B)** Anomalous Hall effect data for device D2, at different
 temperatures (10, 50, 100, 150, 200, 250K). For each temperature, 4
 columns of data are provided - backward field (H), backward Hall
 resistance (Rxy), forward field (H) and forward Hall resistance (Rxy),
 respectively.\ **(C)** Variation of anomalous Hall resistance (RxyAHE) and
 coercivity in the device D2 for varying temperatures (T). These values are
 derived from the curves in SuppFig. 3A and 3B.\ **(D)** Anomalous Hall
 resistance for device D2, for field swept in the plane of the device. Four
 columns of data are provided - backward field (H), backward Hall
 resistance (Rxy), forward field (H) and forward Hall resistance (Rxy),
 respectively. **SuppFig. 4** **(A)** Current induced switching in device
 D2 at 300 K (resistance vs current) for current swept up to a maximum of
 +/- 7 mA. **(B)** Current induced switching in device D2 at 300 K
 (resistance vs current) for current swept up to a maximum of +/- 8 mA.
 Data for this case is the average of four consecutive sweeps. Data
 corresponding to individual sweeps in presented in SuppFig. 5A. **(C)**
 Current induced switching in device D2 at 300 K (resistance vs current)
 for current swept up to a maximum of +/- 9 mA. **(D)** Current induced
 switching in device D2 at 300 K (resistance vs current) for current swept
 up to a maximum of +/- 10 mA. **SuppFig. 5** **(A)** Data for four
 consecutive cyclic current sweeps (loops) at 300 K. Single current coloum
 is provided which is common for all four sweeps. Four coloumns of
 resistance (Rxy) recorded for the four sweeps (loops L1-L4) are provided
 next. **(B)** Data for four consecutive cyclic current sweeps at 305 K.
 Single current coloum is provided which is common for all four sweeps.
 Four coloumns of resistance (Rxy) recorded for the four sweeps are
 provided next. **(C)** Data for four consecutive cyclic current sweeps at
 310 K. Single current coloum is provided which is common for all four
 sweeps. Four coloumns of resistance (Rxy) recorded for the four sweeps are
 provided next. **(D)** Data for four consecutive cyclic current sweeps at
 315 K. Single current coloum is provided which is common for all four
 sweeps. Four coloumns of resistance (Rxy) recorded for the four sweeps are
 provided next. **(E)** Data for four consecutive cyclic current sweeps at
 320 K. Single current coloum is provided which is common for all four
 sweeps. Four coloumns of resistance (Rxy) recorded for the four sweeps are
 provided next. **(F)** Data for four consecutive cyclic current sweeps at
 325 K. Single current coloum is provided which is common for all four
 sweeps. Four coloumns of resistance (Rxy) recorded for the four sweeps are
 provided next. **SuppFig. 6** Time series of Hall resistance measurement -
 time and resistance (Rxy). Two pieces, each 50 second long, are provided
 for temperatures 300 K and 310 K.