Thermal bistability-based method for real-time optimization of ultralow-threshold whispering gallery mode microlasers

TL;DR

This paper introduces a thermal bistability-based technique for real-time optimization of ultralow-threshold whispering gallery mode microlasers, enabling dynamic monitoring and improved control of laser characteristics.

Contribution

The authors develop and demonstrate a novel method leveraging thermal bistability for real-time microlaser optimization, enhancing precision over traditional static approaches.

Findings

Effective real-time monitoring of laser characteristics.

Successful application to a microsphere with submicrowatt threshold.

Validation through comparison with quasi-static thermal measurements.

Abstract

A method based on thermal bistability for ultralow-threshold microlaser optimization is demonstrated. When sweeping the pump laser frequency across a pump resonance, the dynamic thermal bistability slows down the power variation. The resulting line shape modification enables a real-time monitoring of the laser characteristic. We demonstrate this method for a functionalized microsphere exhibiting a submicrowatt laser threshold. This approach is confirmed by comparing the results with a step-by-step recording in quasi-static thermal conditions.