Cavity-based single atom preparation and high-fidelity hyperfine state readout

TL;DR

This paper demonstrates a high-fidelity, rapid hyperfine state readout of a single 87Rb atom coupled to a fiber-based cavity, enabling efficient quantum state detection with minimal disturbance.

Contribution

The work introduces a cavity-based method for preparing and detecting the hyperfine state of a single atom with over 99.92% fidelity in 100 microseconds.

Findings

Achieved hyperfine state readout fidelity >99.92%

Readout time of 100 microseconds

Atom remains trapped after detection

Abstract

We prepare and detect the hyperfine state of a single 87Rb atom coupled to a fiber-based high finesse cavity on an atom chip. The atom is extracted from a Bose-Einstein condensate and trapped at the maximum of the cavity field, resulting in a reproducibly strong atom-cavity coupling. We use the cavity reflection and transmission signal to infer the atomic hyperfine state with a fidelity exceeding 99.92% in a read-out time of 100 microseconds. The atom is still trapped after detection.