Generation of tunable Terahertz radiation using Josephson vortices

TL;DR

This paper presents a method to generate tunable Terahertz radiation using Josephson vortices in modulated superconducting samples, enabling controlled emission through spatial property modulation.

Contribution

It introduces a novel approach to control THz radiation via Josephson vortices in modulated superconductors, including design principles for tunable emitters and photonic crystals.

Findings

Josephson vortices can generate Cherenkov radiation in specific conditions.

Spatial modulation enables transition radiation within targeted frequency windows.

Design strategies for tunable THz emitters are proposed.

Abstract

We propose how to control the THz radiation generated by fast moving Josephson vortices in spatially modulated (either along the c-axis or the ab-plane) samples of Bi-2212 and related superconducting compounds. We show that the JVs moving in a subset of weaker junctions can generate out-of-ab-plane and outside-the-cone Cherenkov radiation. The ab-plane modulation of superconducting properties (achieved, for instance, by ion irradiation lithography) can result in transition radiation within certain frequency windows, i.e., allowing the design of tunable THz emitters and THz photonic crystals.