Dynamics and Resonance Fluorescence from a Superconducting Artificial Atom Doubly Driven by Quantized and Classical Fields

• Main Authors: Ruan, Xinhui, Wang, Jia-Heng, He, Dong, Song, Pengtao, Li, Shengyong, Zhao, Qianchuan, Kuang, L. M, Tsai, Jaw-Shen, Zou, Chang-Ling, Zhang, Jing, Zheng, Dongning, Astafiev, O. V, Liu, Yu-xi, Peng, Zhihui
• Format: Journal Article
• Language: English
• Published: 17-03-2024
• Subjects: Physics - Quantum Physics
• DOI: 10.48550/arxiv.2403.11142

We report an experimental demonstration of resonance fluorescence in a
two-level superconducting artificial atom under two driving fields coupled to a
detuned cavity. One of the fields is classical and the other is varied from
quantum (vacuum fluctuations) to classical one by controlling the photon number
inside the cavity. The device consists of a transmon qubit strongly coupled to
a one-dimensional transmission line and a coplanar waveguide resonator. We
observe a sideband anti-crossing and asymmetry in the emission spectra of the
system through a one-dimensional transmission line, which is fundamentally
different from the weak coupling case. By changing the photon number inside the
cavity, the emission spectrum of our doubly driven system approaches to the
case when the atom is driven by two classical bichromatic fields. We also
measure the dynamical evolution of the system through the transmission line and
study the properties of the first-order correlation function, Rabi oscillations
and energy relaxation in the system. The study of resonance fluorescence from
an atom driven by two fields promotes understanding decoherence in
superconducting quantum circuits and may find applications in superconducting
quantum computing and quantum networks.