Southwest Quantum Information and Technology

Resonance fluorescence from an artificial atom in squeezed vacuum

Presenting Author: Andrew Eddins, Quantum Nanoelectronics Laboratory, University of California, Berkeley
Contributing Author(s): D.M. Toyli, Irfan Siddiqi (Department of Physics, UC Berkeley); S. Puri, S. Boutin, and A. Blais (Departement de Physique, Universite de Sherbrooke); D. Hover, V. Bolkhovsky (MIT Lincoln Laboratory) and W.D. Oliver (MIT Lincoln Laboratory; Research Laboratory of Electronics, MIT).

The accurate prediction of the fluorescence spectrum of a single atom under coherent excitation, comprising canonical phenomena such as the Mollow triplet, is a fundamental success of quantum optics. Despite considerable efforts, experiments demonstrating a strong modification to the resonance fluorescence spectrum resulting from driving an atomic system with non-classical squeezed light have remained elusive, in part due to challenges in efficient coupling. We strongly couple microwave-frequency squeezed light to a superconducting artificial atom and detect the resulting fluorescence using a Josephson traveling-wave parametric amplifier (JTWPA). The observed dramatic dependence of the Mollow triplet on the phase of the squeezed vacuum environment and measurements of subnatural fluorescence linewidths indicate over 3 dB of squeezing below the standard vacuum limit. In addition to realizing two seminal predictions for resonance fluorescence in squeezed vacuum, our work provides simple metrological tools for characterizing microwave frequency squeezed light. This work is supported by the ARO and the ONR.

(Session 5 : Thursday from 5:00 - 7:00 pm)