Light control in a hemicylindrical whispering gallery microcavity-parallel plate waveguide system

TL;DR

This paper demonstrates a novel light control system using a semiconductor hemicylinder and dielectric waveguide separated by a metal layer, enabling efficient mode matching and high Q-factor for compact optical devices.

Contribution

It introduces a new structure combining a semiconductor hemicylinder with a dielectric waveguide for efficient light control and mode matching at sub-wavelength sizes.

Findings

Achieves high Q-factor (~2×10^4) in a compact resonator.

Enables effective light intensity control via small refractive index changes.

Allows size reduction of resonators to the order of the wavelength.

Abstract

We have shown that a structure composed of a semiconductor hemicylinder and a dielectric waveguide separated by a thin metal layer permits efficient and easy light control. In such a system, it is possible to ensure matching between TE and TM modes of a low refractive index waveguide with the corresponding whispering gallery modes of the hemicylinder of a higher refractive index, a circumstance that allows one to reduce the resonator sizes to the order of the exciting wavelength in the vacuum still having rather high Q-factor around 2*10^4. Due to pronounced electro-optical properties of the resonator medium, one is able to effectively control the output light intensity by varying the refractive index of the hemicylinder in the order of 10^(-4).