# Thermo-optical pulsing in a microresonator filtered fiber-laser: a route towards all-optical control and synchronization

## TL;DR

This paper demonstrates slow, microsecond pulse generation in a silica resonator laser system through thermo-optical effects, enabling potential all-optical control and synchronization in laser applications.

## Contribution

It introduces a novel method of generating and controlling microsecond pulses using thermo-optical effects in a nested resonator-fiber laser system, supported by experiments and simulations.

## Key findings

- Pulses with hundreds of kilohertz repetition rate were achieved.
- Pulse properties can be tuned by adjusting fiber cavity parameters.
- Thermal state of the resonator can be externally controlled and sensed.

## Abstract

We report on 'slow' pulsing dynamics in a silica resonator-based laser system: by nesting a high-Q rod-resonator inside an amplifying fiber cavity, we demonstrate that trains of microsecond pulses can be generated with repetition rates in the hundreds of kilohertz. We show that such pulses are produced with a period equivalent to several hundreds of laser cavity roundtrips via the interaction between the gain dynamics in the fiber cavity and the thermo-optical effects in the high-Q resonator. Experiments reveal that the pulsing properties can be controlled by adjusting the amplifying fiber cavity parameters. Our results, confirmed by numerical simulations, provide useful insights on the dynamical onset of complex self-organization phenomena in resonator-based laser systems where thermo-optical effects play an active role. In addition, we show how the thermal state of the resonator can be probed and even modified by an external, counter-propagating optical field, thus hinting towards novel approaches for all-optical control and sensing applications.

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Source: https://tomesphere.com/paper/1903.09095