# Long-path formation in a deformed microdisk laser

## TL;DR

This paper demonstrates a deformed microdisk laser that forms a long optical path, approximately 9.3 times its diameter, using a multiply reflected periodic orbit confined by total internal reflection.

## Contribution

It introduces a novel design of a deformed microdisk with two waveguides that creates a long optical path via a confined periodic orbit, confirmed by spectral and far-field measurements.

## Key findings

- Modes with high quality factors associated with the periodic orbit.
- The device achieves a path length about 9.3 times the microdisk diameter.
- Experimental data confirms the long-path formation in the fabricated device.

## Abstract

An asymmetric resonant cavity can be used to form a path that is much longer than the cavity size. We demonstrate this capability for a deformed microdisk equipped with two linear waveguides, by constructing a multiply reflected periodic orbit that is confined by total internal reflection within the deformed microdisk and outcoupled by the two linear waveguides. Resonant mode analysis reveals that the modes corresponding to the periodic orbit are characterized by high quality factors. From measured spectral and far-field data, we confirm that the fabricated devices can form a path about 9.3 times longer than the average diameter of the deformed microdisk.