Phonon Scattering of Composite Fermions

TL;DR

This paper investigates how acoustic phonons interact with composite fermions in two-dimensional electron systems under strong magnetic fields, deriving the electron-phonon coupling vertex and estimating phonon-related transport properties.

Contribution

It introduces a new derivation of the electron-phonon coupling vertex mediated by the Chern-Simons gauge field in the composite fermion framework.

Findings

Phonon contribution to mobility and thermopower varies with temperature regimes.

Acoustic phonon effects are either suppressed or enhanced compared to zero-field cases.

Results relate phonon effects to surface acoustic wave attenuation coefficients.

Abstract

We study the principal aspects of the interaction between acoustic phonons and two-dimensional electrons in quantizing magnetic fields corresponding to even denominator fractions. Using the composite fermion approach we derive the vertex of the electron-phonon coupling mediated by the Chern-Simons gauge field. We estimate acoustic phonon contribution to electronic mobility, phonon-drag thermopower, and hot electron energy loss rate, which all, depending on the temperature regime, are either proportional to lower powers of T than their zero field counterparts, or enhanced by the same numerical factor as the coefficient of surface acoustic wave attenuation.