Photon emission and absorption of a single ion coupled to an optical fiber-cavity

TL;DR

This paper demonstrates a single ytterbium ion coupled to an optical fiber-cavity, showing efficient photon emission, polarization correlation preservation, and polarization-dependent absorption, advancing quantum light-matter interfaces.

Contribution

It introduces a novel fiber-coupled ion-cavity system with observed polarization-preserving photon emission and absorption properties.

Findings

Photons at 935 nm are mainly emitted into the cavity mode.

Polarization of emitted photons correlates with the ion's spin state.

Enhanced, polarization-dependent absorption observed when injecting coherent light.

Abstract

We present a light-matter interface which consists of a single $^{174}$Yb$^+$ ion coupled to an optical fiber-cavity. We observe that photons at 935 nm are mainly emitted into the cavity mode and that correlations between the polarization of the photon and the spin state of the ion are preserved despite the intrinsic coupling into a single-mode fiber. Complementary, when a faint coherent light field is injected into the cavity mode we find enhanced and polarization dependent absorption by the ion.