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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
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AC Current-Driven Magnetization Switching and Nonlinear Hall Rectification in a Magnetic Topological Insulator
Yuto Kiyonaga1, Masataka Mogi1, Ryutaro Yoshimi2,3
1Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), The University of Tokyo, Tokyo, 113-8656, Japan.
Advanced Materials (Deerfield Beach, Fla.)
|October 14, 2025
Summary
Alternating-current excitation efficiently reverses magnetization in magnetic topological insulators. This process generates tunable nonlinear responses, paving the way for advanced spintronic devices.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Topological insulators possess spin-orbit-coupled surface states enabling efficient spin-orbit torque.
- Current-induced magnetization control is crucial for next-generation spintronic devices.
Purpose of the Study:
- To demonstrate alternating-current (AC) driven magnetization reversal in a semi-magnetic topological insulator.
- To investigate the nonlinear responses and frequency mixing phenomena under AC excitation.
- To explore the potential of AC excitation for multifunctional spintronic applications.
Main Methods:
- Utilized a semi-magnetic topological insulator heterostructure: (Cr,Bi,Sb)2Te3/(Bi,Sb)2Te3.
- Performed time-domain Hall voltage measurements using an oscilloscope.
- Applied Fourier analysis to time-varying Hall voltage signals.
- Investigated current-voltage characteristics under dual-frequency excitation.
Main Results:
- Achieved AC-driven magnetization reversal with a low threshold current density (1.5 × 10^9 A m^-2).
- Observed a nonlinear and rectified Hall response during magnetization reversal.
- Identified higher-harmonic signals and a rectified direct-current (DC) component in Hall voltage.
- Demonstrated frequency mixing via hysteretic current-voltage characteristics under dual-frequency excitation.
Conclusions:
- AC excitation offers an efficient method for magnetization switching in magnetic topological insulators.
- The observed nonlinear responses and frequency mixing provide new avenues for spintronic device functionalities.
- This work presents a pathway towards energy-efficient spintronic memory, signal processing, and frequency conversion devices.
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