Ground State Electroluminescence

TL;DR

This paper reveals a novel quantum electroluminescence phenomenon occurring in systems with ultrastrong light-matter coupling, where current-driven emission involves extracting photons from the dressed ground state, distinct from standard electroluminescence.

Contribution

It introduces and characterizes a new form of quantum radiation emitted under ultrastrong coupling conditions, expanding understanding of light emission mechanisms in quantum systems.

Findings

Identification of quantum radiation from the dressed ground state

Distinct features separating it from standard electroluminescence

Potential implications for quantum light sources

Abstract

Electroluminescence, the emission of light in the presence of an electric current, provides information on the allowed electronic transitions of a given system. It is commonly used to investigate the physics of strongly-coupled light-matter systems, whose eigenfrequencies are split by the strong coupling with the photonic field of a cavity. Here we show that, together with the usual electroluminescence, systems in the ultrastrong light-matter coupling regime emit a uniquely quantum radiation when a flow of current is driven through them. While standard electroluminescence relies on the population of excited states followed by spontaneous emission, the process we describe herein extracts bound photons by the dressed ground state and it has peculiar features that unequivocally distinguish it from usual electroluminescence.