Design and Fabrication of Ultrahigh Q Chip-Based Silica WGM Micro-resonators for Single-Atom Cavity-QED

TL;DR

This paper presents a model-based method for designing and fabricating ultrahigh Q silica whispering-gallery mode microresonators with small mode-volumes, suitable for single-atom cavity-QED applications, achieving qualities up to 1.7×10^8.

Contribution

It introduces a theoretical and experimental framework for creating small, ultrahigh Q WGM microresonators with customizable geometries for quantum optics.

Findings

Achieved Q factors up to 1.7×10^8 at 780nm.

Developed a theoretical model for tailoring resonator geometry.

Demonstrated fabrication of various geometries from toroidal to micro-spheres.

Abstract

Of the many applications of whispering-gallery mode (WGM) microresonators, Single-atom cavity-QED poses the most extreme demands on mode-volume and quality factor. Here we present a model-based procedure for the fabrication of small mode-volume ultrahigh Q silica WGM microresonators of varying geometries, from toroidal to micro-spheres. We experimentally demonstrate WGM resonators with ultra-high qualities as high as $1.7\times 10^8$ at 780nm. We present a theoretical model that allows tailoring the recipe to attain the desired geometry of the fabricated WGM microresonators.