Electrometry of a single resonator mode at a hybrid Rydberg-atom superconducting-circuit interface

Hybrid approaches to quantum information processing involve interfacing quantum systems with complementary characteristics, e.g., superconducting circuits for fast quantum-state manipulation, and gas-phase atoms or molecules for long coherence times [1]. In this context we recently demonstrated a coherent interface between helium Rydberg atoms and microwave fields in a superconducting coplanar waveguide resonator [2,3]. Here, we report the extension of this work to perform electrometry at this interface, using the atoms to probe the spatial distribution of the microwave field of a single resonator mode, and precisely measure static electric fields by Ramsey spectroscopy. These results have elucidated sources of decoherence of the atomic states, and in the interaction of the atoms with the resonator field. They pave the way for the implementation of long-coherence-time quantum memories and optical-to-microwave photon conversion in this hybrid system.

 

[1] Rabl, DeMille, Doyle, Lukin, Schoelkopf and Zoller, Phys. Rev. Lett. 97, 033003 (2006)

[2] Morgan and Hogan, Phys. Rev. Lett. 124, 193604 (2020)

[3] Walker, Morgan and Hogan, Appl. Phys. Lett. 114 204001 (2020)