Light-matter interaction in open cavities with dielectric stacks

TL;DR

This paper presents an exact model for the dipole coupling strength in open optical cavities with multilayer dielectric mirrors, accounting for complex effects on mode volume and resonance.

Contribution

It introduces a comprehensive theoretical framework for evaluating light-matter interaction in open cavities with dielectric stacks, including variable resonance and mirror design parameters.

Findings

Coupling strength depends on cavity length and dielectric mirror design.

Effective mode volume can significantly differ from geometric length in short cavities.

Radiation field is strongest within the dielectric mirror itself.

Abstract

We evaluate the exact dipole coupling strength between a single emitter and the radiation field within an optical cavity, taking into account the effects of multilayer dielectric mirrors. Our model allows one to freely vary the resonance frequency of the cavity, the frequency of light or atomic transition addressing it and the design wavelength of the dielectric mirror. The coupling strength is derived for an open system with unbound frequency modes. For very short cavities, the effective length used to determine their mode volume and the lengths defining their resonances are different, and also found to diverge appreciably from their geometric length, with the radiation field being strongest within the dielectric mirror itself. Only for cavities much longer than their resonant wavelength does the mode volume asymptotically approach that normally assumed from their geometric length.