Ultra-Strong Coupling Effects with Quantum Metamaterials

TL;DR

This paper explores a semiconductor quantum metamaterial that exhibits ultra-strong coupling effects, supporting a new plasma resonance mode with significant vacuum Rabi splitting, advancing the understanding of light-matter interactions in engineered materials.

Contribution

It introduces a novel quantum metamaterial supporting a collective plasma resonance mode with ultra-strong coupling characteristics, demonstrated by large vacuum Rabi splitting.

Findings

Supports a new guided collective plasma resonance mode

Demonstrates ultra-strong coupling with a 65 meV vacuum Rabi splitting

Achieves a coupling strength of 21% of the intersubband energy

Abstract

We study a semiconductor based quantum metamaterial which has the optical characteristics of a metal in two directions, but behaves like a collection of artificial atoms, whose properties can be designed in using quantum theory, in the third. We find that it supports a new type of guided collective plasma resonance (CPR) mode which exhibits efficient optical coupling and long propagation distances. Furthermore, the coupling of the CPR mode with the artificial atom transition leads to a case of Ultra Strong Coupling, demonstrated by a large vacuum Rabi splitting of 65 meV, a sizable fraction (21 percent), of the bare intersubband energy.