Large Bragg Reflection from One-Dimensional Chains of Trapped Atoms Near a Nanoscale Waveguide

TL;DR

This paper demonstrates large Bragg reflection from ordered chains of cold atoms near a nanoscale waveguide, achieving up to 75% reflectance, and explores the effects of lattice period and polarization on photon transport.

Contribution

It presents the first experimental realization of high reflectance from atom chains near a nanofiber, highlighting control over photon reflection and waveguide properties.

Findings

Achieved up to 75% reflectance with 2000 atoms

Observed polarization-dependent reflection effects

Demonstrated control of photon transport in 1D waveguides

Abstract

We report experimental observations of large Bragg reflection from arrays of cold atoms trapped near a one-dimensional nanoscale waveguide. By using an optical lattice in the evanescent field surrounding a nanofiber with a period nearly commensurate with the resonant wavelength, we observe a reflectance of up to 75% for the guided mode. Each atom behaves as a partially-reflecting mirror and an ordered chain of about 2000 atoms is sufficient to realize an efficient Bragg mirror. Measurements of the reflection spectra as a function of the lattice period and the probe polarization are reported. The latter shows the effect of the chiral character of nanoscale waveguides on this reflection. The ability to control photon transport in 1D waveguides coupled to spin systems would enable novel quantum network capabilities and the study of many-body effects emerging from long-range interactions.