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Magnetism Induced by Periodically Driven Nonmagnetic Impurities on Surfaces with Spin-Orbit Coupling
Malen Etxeberria-Etxaniz1, Andrés Arnau2,3,4, Asier Eiguren1,4,5
1Universidad del País Vasco UPV/EHU, Departamento de Física, 48080 Leioa, Spain.
Physical Review Letters
|May 15, 2026
Summary
This study reveals that Rashba spin-orbit systems can develop oscillating magnetization without external magnetic fields. This phenomenon arises from time-periodic potentials and Fermi surface spin polarization.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Spintronics
Background:
- The Rashba spin-orbit interaction is crucial in spintronics.
- Understanding nonequilibrium phenomena in quantum systems is essential.
Purpose of the Study:
- To investigate induced magnetization in Rashba systems under time-periodic potentials.
- To explore the system's response without external magnetic fields.
Main Methods:
- Floquet Green's function method
- Keldysh formalism
- Nonequilibrium steady-state calculations
- Fourier decomposition in nonlocal momentum space
Main Results:
- An oscillating magnetization density is induced, even without magnetic fields.
- The magnetization exhibits rich structural properties.
- The origin is linked to Fermi surface spin polarization and system dynamics.
Conclusions:
- Time-periodic potentials can induce magnetization in Rashba systems.
- The findings offer insights into dynamical spin polarization and magnetic field generation.
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