Evolution of coherent waves driving a single artificial atom

TL;DR

This paper investigates how a strongly coupled superconducting artificial atom influences the evolution of coherent electromagnetic waves in a waveguide, revealing detailed atom-field interaction dynamics through spectral and correlation analysis.

Contribution

It provides a detailed analysis of the time-dependent behavior of transmitted fields and their spectra, demonstrating how field evolution encodes atom dynamics using input-output theory.

Findings

Time evolution of fields reveals atom dynamics

Spectral analysis captures atom-field interaction

Incoherent radiation dynamics deduced from correlation functions

Abstract

An electromagnetic wave propagating through a waveguide with a strongly coupled superconducting artificial two-level atom exhibits an evolving superposition with the atom. The Rabi oscillations in the atom result from a single excitation-relaxation, corresponding to photon absorption and stimulated emission from/to the field. In this study, we investigate the time-dependent behavior of the transmitted field and extract its spectra. The scattered fields are described using input-output theory. We demonstrate that the time evolution of the propagating fields, due to interaction, encapsulates all information about the atom. Additionally, we deduce the dynamics of the incoherent radiation component from the measured first-order correlation function of the field.