Tunable Broadband Transparency of Macroscopic Quantum Superconducting Metamaterials

TL;DR

This paper introduces a macroscopic quantum superconducting metamaterial that achieves broadband transparency through a novel nonlinear mechanism, allowing for highly tunable and hysteretic control of transparency for advanced applications.

Contribution

It presents a new nonlinear mechanism for broadband transparency in superconducting metamaterials, enabling easy, hysteretic, and in situ tunability beyond conventional EIT-based methods.

Findings

Near complete disappearance of resonant absorption observed experimentally

Transparency can be tuned on/off by magnetic fields, temperature, and history

Hysteretic 100% tunability demonstrated

Abstract

Narrow-band invisibility in an otherwise opaque medium has been achieved by electromagnetically induced transparency (EIT) in atomic systems. The quantum EIT behaviour can be classically mimicked by specially engineered metamaterials via carefully controlled interference with a "dark mode". However, the narrow transparency window limits the potential applications that require a tunable wide-band transparent performance. Here, we present a macroscopic quantum superconducting metamaterial with manipulative self-induced broadband transparency due to a qualitatively novel nonlinear mechanism that is different from conventional EIT or its classical analogs. A near complete disappearance of resonant absorption under a range of applied rf flux is observed experimentally and explained theoretically. The transparency comes from the intrinsic bi-stability and can be tuned on/ off easily by altering rf and dc magnetic fields, temperature and history. Hysteretic in situ 100% tunability of transparency paves the way for auto-cloaking metamaterials, intensity dependent filters, and fast-tunable power limiters.