Entanglement-enhanced detection of single-photon scattering events

TL;DR

This paper introduces an entanglement-based method to detect single-photon scattering events on broad optical transitions with high sensitivity, overcoming previous detection challenges and enabling advances in spectroscopy and quantum information.

Contribution

The authors develop a novel entanglement-enhanced technique to detect single-photon scattering on broad transitions, extending sensitivity beyond narrow-line detection methods.

Findings

Successfully demonstrated detection of single-photon scattering events

Achieved high sensitivity using entangled states to amplify momentum kicks

Potential applications in atomic/molecular spectroscopy and quantum computing

Abstract

The ability to detect the interaction of light and matter at the single-particle level is becoming increasingly important for many areas of science and technology. The absorption or emission of a photon on a narrow transition of a trapped ion can be detected with near unit probability, thereby enabling the realization of ultra-precise ion clocks and quantum information processing applications. Extending this sensitivity to broad transitions is challenging due to the difficulty of detecting the rapid photon scattering events in this case. Here, we demonstrate a technique to detect the scattering of a single photon on a broad optical transition with high sensitivity. Our approach is to use an entangled state to amplify the tiny momentum kick an ion receives upon scattering a photon. The method should find applications in spectroscopy of atomic and molecular ions and quantum information processing.