Cavity-enhanced channeling of emission from an atom into a nanofiber

TL;DR

This paper demonstrates that a nanofiber with fiber-Bragg-grating mirrors can significantly enhance and channel atomic emission into guided modes, achieving high efficiency and strong coupling even with moderate finesse and large cavity length.

Contribution

It introduces a novel cavity design using FBG mirrors on a nanofiber to enhance atom-photon interactions, enabling high emission channeling and strong coupling at moderate finesse.

Findings

Up to 94% of emission channeled into guided modes.

Vacuum Rabi oscillations occur with moderate finesse.

Strong coupling achieved in large cavities.

Abstract

We study spontaneous emission of an atom near a nanofiber with two fiber-Bragg-grating (FBG) mirrors. We show that the coupling between the atom and the guided modes of the nanofiber can be significantly enhanced by the FBG cavity even when the cavity finesse is moderate. We find that, when the fiber radius is 200 nm and the cavity finesse is about 30, up to 94% of spontaneous emission from the atom can be channeled into the guided modes in the overdamped-cavity regime. We show numerically and analytically that vacuum Rabi oscillations and strong coupling can occur in the FBG cavity even when the cavity finesse is moderate (about 30) and the cavity length is large (on the order of 10 cm to 1 m), unlike the case of planar and curved Fabry-Perot cavities.