Low Loss and Magnetic Field-tuned Superconducting THz Metamaterial

TL;DR

This paper demonstrates a superconducting THz metamaterial with high quality factors and magnetic field tuning capabilities, showing potential for low-loss and tunable THz applications.

Contribution

It introduces a superconducting Nb film-based THz metamaterial with high quality factors and magnetic field tuning, a novel approach compared to existing electric, optical, and thermal tuning methods.

Findings

Quality factors at 132 GHz and 450 GHz are three times higher than metal counterparts.

Magnetic field tuning of the superconducting THz metamaterial is successfully demonstrated.

Superconducting THz MM offers low loss and tunability advantages for THz technologies.

Abstract

Superconducting terahertz (THz) metamaterial (MM) made from superconducting Nb film has been investigated using a continuous-wave THz spectroscopy with a superconducting split-coil magnet. The obtained quality factors of the resonant modes at 132 GHz and 450 GHz are about three times as large as those calculated for a metal THz MM operating at 1 K, which indicates that superconducting THz MM is a very nice candidate to achieve low loss performance. In addition, the magnetic field-tuning on superconducting THz MM is also demonstrated, which offer an alternative tuning method apart from the existed electric, optical and thermal tuning on THz MM.