Microreversibility, fluctuation relations, and response properties in 1D Kitaev Chain

TL;DR

This paper analytically investigates energy and particle transport in an open 1D Kitaev chain, revealing how fluctuation relations and response properties depend on symmetry breaking and energy conservation, with implications for thermoelectricity.

Contribution

It provides an analytical calculation of the cumulant generating function and explores fluctuation relations in the Kitaev chain, connecting symmetry breaking to transport properties.

Findings

Different fluctuation relations in various parameter regions.

Analytical expression for maximum work power.

Consistency of second-order response with fluctuation relations.

Abstract

We analytically calculate the cumulant generating function of energy and particle transport in an open 1D Kitaev chain by utilizing the Keldysh technique. The joint distribution of particle and energy currents obeys different fluctuation relations in different regions of the parameter space as a result of $U$(1) symmetry breaking and energy conservation. We discuss the thermoelectricity of the Kitaev chain as a three terminal system and derive an analytical expression of the maximum work power. The response theory up to the second order is explicitly checked, and the result is consistent with the relations derived from the fluctuation relation.