Interfacial Modulation of Spin-Orbit Torques Induced by Two-Dimensional van der Waals Material ZrSe₃

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spintronics

Background:

• Two-dimensional van der Waals (2D vdW) materials are crucial for spin-orbit torque (SOT) devices.
• ZrSe3 exhibits low crystal symmetry and high spin Hall conductivity, making it promising for low-power SOT applications.

Purpose of the Study:

• Investigate the interfacial effects of SOTs.
• Analyze current-induced magnetization switching in ZrSe3/Py and ZrSe3/Cu/Py heterostructures.
• Evaluate the impact of copper (Cu) intercalation on SOT efficiency.

Main Methods:

• Spin-torque ferromagnetic resonance (ST-FMR) to measure SOT efficiencies.
• Magneto-optical Kerr effect (MOKE) microscopy for current-driven magnetization switching.
• Theoretical calculations to understand interfacial electronic properties.

Main Results:

• Cu intercalation modulated the ratio of damping-like torque (τB) to field-like torque (τA), decreasing the τB component.
• SOT efficiency increased from 3.05 to 5.21 with Cu intercalation.
• Cu intercalation transformed ZrSe3 from semiconductor to conductor, reducing Schottky barriers and enhancing spin current transmission.
• ZrSe3/Cu/Py structures showed reduced critical current density compared to ZrSe3/Py.

Conclusions:

• Cu intercalation effectively enhances SOT efficiency in ZrSe3-based heterostructures.
• The optimized ZrSe3/Cu/Py structures offer potential for lower power consumption in spintronic devices.