Resonance fluorescence spectra of a driven Kerr nonlinear resonator

TL;DR

This paper investigates the resonance fluorescence spectra of a driven Kerr nonlinear resonator through both theoretical derivation and experimental measurement, revealing characteristic spectral features and their physical origins.

Contribution

It provides a comprehensive theoretical framework and experimental validation for the resonance fluorescence spectra of a strongly driven Kerr nonlinear resonator, highlighting features beyond the two-level approximation.

Findings

Decreased center-peak intensity in spectra

Asymmetric sideband peaks observed

Quantitative agreement between theory and experiment

Abstract

Resonance fluorescence spectra of a driven Kerr nonlinear resonator is investigated both theoretically and experimentally. When the Kerr nonlinear resonator is driven strongly such that the induced Rabi frequency is comparable to or larger than the Kerr nonlinearity, the system cannot be approximated as a two-level system. We theoretically derive characteristic features in the fluorescence spectra such as the decrease of the center-peak intensity and the asymmetric sideband peaks in the presence of finite dephasing. Those features are consistently explained by the population of the initial dressed state and its transition matrix element to the final dressed state of the transition corresponding to each peak. Finally, we experimentally measure the resonance fluorescence spectra of a driven superconducting Kerr nonlinear resonator and find a quantitative agreement with our theory.