Realizing arbitrary trapping potentials for light via direct laser writing of mirror surface profiles

TL;DR

This paper presents a novel method for creating arbitrary trapping potentials for light by directly laser writing mirror surface profiles, enabling precise control of photon behavior in microcavities for quantum experiments.

Contribution

It introduces a heat-induced mirror microstructuring technique to shape optical resonator geometries for variable potential structures in microcavity photon experiments.

Findings

Demonstrated spatial redistribution of thermal photons in structured microcavities.

Observed Bose-Einstein condensation in a spatially split photon ground state.

Showed control of photon thermalization via tailored mirror surface profiles.

Abstract

The versatility of quantum gas experiments greatly benefits from the ability to apply variable potentials. Here we describe a method which allows the preparation of potential structures for microcavity photons via spatially selective deformation of optical resonator geometries with a heat induced mirror surface microstructuring technique. We investigate the thermalization of a two-dimensional photon gas in a dye-filled microcavity composed of the custom surface-structured mirrors at wavelength-scale separation. Specifically, we describe measurements of the spatial redistribution of thermal photons in a coupled double-ridge structure, where photons form a Bose-Einstein condensate in a spatially split ground state, as a function of different pumping geometries.