Emission of continuous coherent terahertz waves with tunable frequency by intrinsic Josephson junctions

TL;DR

This paper proposes a simulation-based mechanism for generating tunable continuous coherent terahertz waves using intrinsic Josephson junctions in high-temperature superconductors, involving fluxon-induced plasma oscillations and energy emission.

Contribution

It introduces a novel simulation approach demonstrating how fluxon flow in stacked Josephson junctions can produce tunable terahertz emissions.

Findings

Fluxon flow induces voltage and oscillating current.

Josephson plasma forms standing waves in the cavity.

Energy is emitted as continuous terahertz waves.

Abstract

We present a mechanism for emission of electromagnetic terahertz waves by simulation. High $T_{c}$ superconductors form naturally stacked Josephson junctions. When an external current and a magnetic field are applied to the sample, fluxon flow induces voltage. The voltage creates oscillating current through the Josephson effect and the current excites the Josephson plasma. The sample works as a cavity, and the input energy is stored in a form of standing wave of the Josephson plasma. A part of the energy is emitted as terahertz waves.