Computer Simulation on Terahertz Emission from Intrinsic Josephson Junctions of High-T_c Superconductors

TL;DR

This paper uses numerical simulations to study terahertz emission from high-temperature superconductor Josephson junctions, revealing tunable emission properties and electromagnetic wave transmission.

Contribution

It introduces a detailed numerical approach to analyze terahertz emission from intrinsic Josephson junctions in high-$T_c$ superconductors, highlighting tunability and wave transmission.

Findings

Terahertz-range cavity resonances observed in Josephson junctions.

Electromagnetic waves can transmit from junctions into space.

Emitted energy reaches approximately 400 W/cm².

Abstract

Solving coupled nonlinear sine-Gordon equations and Maxwell equations numerically, we study the electromagnetic and superconducting properties of the single crystal of high-$T_c$ superconductor $\rm{Bi_2Sr_2CaCu_2O_{8+\delta}}$ with a static magnetic field applied parallel to the $ab$-plane and a dc current fed in along the c-axis. Cavity resonances of transverse plasma occur in the intrinsic Josephson junctions with frequencies in terahertz regime. It is revealed that the electromagnetic wave can transmit from the junctions into space. The emitted energy counted by the Poynting vector is about $400\rm{W/cm^2}$. The frequency as well as the energy of emission can be tuned almost continuously by the current and magnetic field.