# Generation of Teraherz Oscillations by Thin Superconducting Film in Fluctuation Regime

## TL;DR

This paper derives analytical expressions for the conductivity of superconducting films near the critical temperature, revealing conditions for negative differential conductivity that can generate Terahertz oscillations.

## Contribution

It provides explicit formulas for superconducting film conductivity in electric fields, linking negative differential conductivity to Terahertz oscillation generation.

## Key findings

- Negative differential conductivity occurs near critical temperature.
- Oscillation frequency is proportional to critical temperature.
- Results can enable Terahertz generator development.

## Abstract

Explicit analytical expressions for conductivity of a superconducting film above and below critical temperature in an arbitrary electric field are derived in the frameworks of the time dependent Ginzburg-Landau theory. It is confirmed that slightly below critical temperature the differential conductivity of superconducting film can become negative for small enough values of electric field. This fact may cause generation of electromagnetic oscillations if the superconducting film is appropriately coupled of with a resonator. Their maximal frequency is proportional to the value of critical temperature of superconducting transition. The obtained results can stimulate the development of Terahertz generators on the basis of high temperature superconducting films.