Spin-orbit coupling and electron spin resonance for interacting electrons in carbon nanotubes

TL;DR

This paper reviews the theoretical understanding of spin-orbit coupling and electron spin resonance in carbon nanotubes, emphasizing the role of electron-electron interactions and predicting distinctive ESR spectral features.

Contribution

It provides a comprehensive analysis combining effective field theory and numerical methods to describe ESR spectra in interacting electrons within carbon nanotubes.

Findings

Double peak ESR spectrum predicted for single-wall nanotubes.

Numerical studies confirm the theoretical predictions.

Additional features are identified in finite-size samples.

Abstract

We review the theoretical description of spin-orbit scattering and electron spin resonance in carbon nanotubes. Particular emphasis is laid on the effects of electron-electron interactions. The spin-orbit coupling is derived, and the resulting ESR spectrum is analyzed both using the effective low-energy field theory and numerical studies of finite-size Hubbard chains and two-leg Hubbard ladders. For single-wall tubes, the field theoretical description predicts a double peak spectrum linked to the existence of spin-charge separation. The numerical analysis basically confirms this picture, but also predicts additional features in finite-size samples.