Determination of density of states of thin high-$T_c$ films by FET type microstructures

TL;DR

This paper proposes a straightforward electronic method using FET microstructures to determine the density of states in thin high-$T_c$ superconducting films by analyzing harmonic voltages.

Contribution

It introduces a novel experimental technique employing harmonic measurements to extract the density of states in high-$T_c$ superconducting films.

Findings

Method successfully measures the logarithmic derivative of the density of states.

The technique provides a new way to fit band structure parameters.

Experimental setup is simple and effective for thin superconducting films.

Abstract

A simple electronic experiment with a field effect transistor type microstructure is suggested. The thin superconductor layer is the source-drain channel of the layered structure where an AC current is applied. It is necessary to measure the second harmonic of the source-gate voltage and third harmonic of the source-drain voltage. The electronic measurement can give the logarithmic derivative of the density of states which is an important parameter for fitting of parameters of the band structures.