Simulations of atomic trajectories near a dielectric surface

TL;DR

This paper develops a semiclassical model to simulate atomic trajectories near a dielectric surface, accounting for surface effects like Casimir-Polder shifts, and analyzes experimental atomic transit events in microtoroidal resonators.

Contribution

It introduces a novel semiclassical simulation framework that incorporates surface-induced level shifts for atoms near microtoroids, extending understanding of atom-cavity interactions.

Findings

Atoms can achieve strong coupling at ~100 nm from the surface

Surface effects significantly influence atomic motion and detection

Simulation aligns with experimental transit event observations

Abstract

We present a semiclassical model of an atom moving in the evanescent field of a microtoroidal resonator. Atoms falling through whispering-gallery modes can achieve strong, coherent coupling with the cavity at distances of approximately 100 nanometers from the surface; in this regime, surface-induced Casmir-Polder level shifts become significant for atomic motion and detection. Atomic transit events detected in recent experiments are analyzed with our simulation, which is extended to consider atom trapping in the evanescent field of a microtoroid.