Observation of collapse and revival in a superconducting atomic frequency comb

TL;DR

This paper demonstrates the observation of collapse and revival phenomena in a superconducting atomic frequency comb, created by strongly coupled artificial atoms, revealing collective quantum dynamics with potential quantum memory applications.

Contribution

It introduces a superconducting atomic frequency comb formed by artificial atoms strongly coupled to a resonator, showcasing revival dynamics due to rephasing of qubits, a novel observation in this system.

Findings

Periodic microwave pulses from a single excitation

Rephasing of five superconducting qubits causes revival

Potential for quantum memory and on-chip pulse generation

Abstract

Recent advancements in superconducting circuits have enabled the experimental study of collective behavior of precisely controlled intermediate-scale ensembles of qubits. In this work, we demonstrate an atomic frequency comb formed by individual artificial atoms strongly coupled to a single resonator mode. We observe periodic microwave pulses that originate from a single coherent excitation dynamically interacting with the multi-qubit ensemble. We show that this revival dynamics emerges as a consequence of the constructive and periodic rephasing of the five superconducting qubits forming the vacuum Rabi split comb. In the future, similar devices could be used as a memory with in-situ tunable storage time or as an on-chip periodic pulse generator with non-classical photon statistics.