Controlled Manipulation of Mode Splitting in an Optical Microcavity by Two Rayleigh Scatterers

TL;DR

This paper demonstrates precise control over mode splitting in an optical microresonator using two nanoprobes, enabling tunable mode interactions and transitions with potential applications in sensing and photonics.

Contribution

It introduces a method to manipulate mode splitting in microresonators with two nanoprobes, providing a tunable platform for studying mode interactions.

Findings

Mode splitting can be tuned simultaneously or individually.

Modes can cross or anti-cross in frequency and linewidth.

Transition between standing wave and traveling wave modes observed.

Abstract

We report controlled manipulation of mode splitting in an optical microresonator coupled to two nanoprobes. It is demonstrated that, by controlling the positions of the nanoprobes, the split modes can be tuned simultaneously or individually and experience crossing or anti-crossing in frequency and linewidth. A tunable transition between standing wave mode and travelling wave mode is also observed. Underlying physics is discussed by developing a two-scatterer model which can be extended to multiple scatterers. Observed rich dynamics and tunability of split modes in a single microresonator will find immediate applications in optical sensing, opto-mechanics, filters and will provide a platform to study strong light-matter interactions in two-mode cavities.