109 citations · 165 across the 10 of their papers we have counts for
4 papers · 1 filter
High-frequency suppression of inductive coupling between flux qubit and transmission line resonator
Sahel Ashhab, Ziqiao Ao, Fumiki Yoshihara +2
We perform theoretical calculations to investigate the naturally occurring high-frequency cutoff in a circuit comprising a flux qubit coupled inductively to a transmission line res…
Extremely large Lamb shift in a deep-strongly coupled circuit QED system with a multimode resonator
Ziqiao Ao, Sahel Ashhab, Fumiki Yoshihara +5
We report experimental and theoretical results on the extremely large Lamb shift in a multimode circuit quantum electrodynamics (QED) system in the deep-strong coupling (DSC) regim…
Deterministic three-photon down-conversion by a passive ultrastrong cavity-QED system
Kazuki Koshino, Tomohiro Shitara, Ziqiao Ao +1
In ultra- and deep-strong cavity quantum electrodynamics (QED) systems, many intriguing phenomena that do not conserve the excitation number are expected to occur. In this study, w…
Inversion of Qubit Energy Levels in Qubit-Oscillator Circuits in the Deep-Strong-Coupling Regime
Fumiki Yoshihara, Tomoko Fuse, Ziqiao Ao +6
We report on experimentally measured light shifts of superconducting flux qubits deep-strongly coupled to LC oscillators, where the coupling constants are comparable to the qubit a…