Thermopower and the Mott formula for a Majorana edge state

TL;DR

This paper investigates the thermoelectric properties of Majorana edge states, deriving a Mott formula that relates thermopower to conductance, enabling temperature inference of Majorana states through combined measurements.

Contribution

It extends the Mott formula to Majorana edge states and proposes a method to determine their temperature via thermoelectric measurements.

Findings

Non-zero thermopower can exist for Majorana edge states.

The Mott formula relates thermopower to differential conductance in this context.

Measurement of voltage and conductance can infer the Majorana edge state temperature.

Abstract

We study the thermoelectric effect between a conducting lead and a Majorana edge state. In the tunneling limit, we first use the Landuaer-Buttiker formalism to derive the Mott formula relating the thermopower and the differential conductance between a conducting lead and a superconductor. When the tunneling takes place between a conducting lead and a Majorana edge state, we show that a non-vanishing thermopower can exist. Combining measurements of the differential conductance and the voltage difference induced by the temperature difference between the conducting lead and the edge state, the Mott formula provides a unique way to infer the temperature of the Majorana edge state.