Diffusion Thermopower at Even Denominator Fractions

TL;DR

This paper calculates the diffusion thermopower in composite fermion quantum Hall states at even denominator fractions, highlighting the dominant logarithmic temperature corrections affecting thermopower behavior and suggesting experimental observability.

Contribution

It introduces a detailed calculation of thermopower at even denominator fractions using the composite fermion framework, emphasizing the role of conductivity corrections.

Findings

Logarithmic temperature corrections dominate thermopower deviations.

Enhanced thermopower magnitude compared to zero field case.

Potential for experimental observation with current techniques.

Abstract

We compute the electron diffusion thermopower at compressible Quantum Hall states corresponding to even denominator fractions in the framework of the composite fermion approach. It is shown that the deviation from the linear low temperature behavior of the termopower is dominated by the logarithmic temperature corrections to the conductivity and not to the thermoelectric coefficient, although such terms are present in both quantities. The enhanced magnitude of this effect compared to the zero field case may allow its observation with the existing experimental techniques.