# Dynamics of trapped atoms around an optical nanofiber probed through polarimetry

## TL;DR

This paper introduces a non-destructive polarimetry technique to characterize atomic trapping potentials around an optical nanofiber by analyzing polarization changes in a probe beam caused by atomic motion.

## Contribution

It presents a novel method using polarization rotation measurements to rapidly and non-destructively determine trapping frequencies of atoms near an optical nanofiber.

## Key findings

- Successful measurement of trapping frequencies through polarization rotation.
- Demonstration of a non-destructive, real-time characterization method.
- Insights into atomic motion dynamics around the nanofiber.

## Abstract

The evanescent field outside an optical nanofiber (ONF) can create optical traps for neutral atoms. We present a non-destructive method to characterize such trapping potentials. An off-resonance linearly polarized probe beam that propagates through the ONF experiences a slow axis of polarization produced by trapped atoms on opposite sides along the ONF. The transverse atomic motion is imprinted onto the probe polarization through the changing atomic index of of refraction. By applying a transient impulse, we measure a time-dependent polarization rotation of the probe beam that provides both a rapid and non-destructive measurement of the optical trapping frequencies.