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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Chiral spin waves in Fermi liquids with spin-orbit coupling.
Ali Ashrafi1, Dmitrii L Maslov
1Department of Physics, University of Florida, P.O. Box 118440, Gainesville, Florida 32611-8440, USA.
Physical Review Letters
|February 2, 2013
Summary
We predict chiral spin waves, collective magnetic excitations, in 2D Fermi liquids with spin-orbit coupling. These modes behave as particles with tunable effective masses, observable via microwave absorption.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Materials Science
Background:
- Spin-orbit coupling (SOC) is crucial for spintronic devices.
- Understanding collective magnetic excitations in 2D systems is key for novel functionalities.
Purpose of the Study:
- To predict and characterize chiral spin waves in 2D Fermi liquids with Rashba or Dresselhaus SOC.
- To explore the influence of electron-electron interactions on these spin waves.
Main Methods:
- Phenomenological Landau theory to describe magnetization dynamics.
- Klein-Gordon equations for long-wavelength dynamics.
- Dyson equation for determining the spin-chiral mode spectrum.
Main Results:
- Prediction of chiral spin waves as particle-like excitations.
- Effective masses of these excitations depend on electron-electron interaction strength.
- Spectrum of spin-chiral modes determined for various wavelengths.
Conclusions:
- Chiral spin waves are a novel collective mode in 2D Fermi liquids with SOC.
- Proposed experimental observation via microwave absorption using confined standing waves.
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