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Updated: May 24, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Effects of the Rashba spin-orbit coupling on Hofstadter's butterfly
1Posgrado de Ciencias Fisicas, Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, A Postal 356, Ensenada, Baja, California, 22835, Mexico. sukey@cnyn.unam.mx
Summary
Rashba spin-orbit coupling influences the Hofstadter spectrum in 2D electron systems. Spin-orbit interaction increases fractal complexity and leads to fractal-like spin polarization, affecting electron states.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
Background:
- The Hofstadter spectrum describes electron behavior in a magnetic field.
- Spin-orbit coupling significantly impacts electronic properties.
Purpose of the Study:
- To investigate Rashba spin-orbit coupling's effect on the Hofstadter spectrum.
- To analyze the impact on energy spectrum and spin polarization.
Main Methods:
- Derivation of generalized coupled Harper spin-dependent equations.
- Solving for energy spectrum and spin polarization.
- Analysis of fractal geometry using correlation dimension.
Main Results:
- Spin-orbit coupling quadratically increases fractal complexity.
- Spin polarization exhibits fractal-like behavior with magnetic flux.
- Spin localization observed for ground states, while excited states show uniform spin distribution.
Conclusions:
- Rashba spin-orbit coupling introduces fractal characteristics to the Hofstadter butterfly.
- Spin polarization dynamics are significantly altered by spin-orbit interaction.
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