Bringing short-lived dissipative Kerr soliton states in microresonators into a steady state

TL;DR

This paper introduces a power modulation technique to stabilize short-lived dissipative Kerr soliton states in microresonators, enabling long-term, thermally self-locked solitons for improved optical frequency combs.

Contribution

A novel power kicking method that stabilizes initially short-lived solitons in microresonators, surpassing previous techniques that relied solely on laser scan adjustments.

Findings

Short-lived solitons can be stabilized into steady states.

Steady-state solitons can persist for hours.

The method effectively compensates thermal effects during soliton formation.

Abstract

Dissipative Kerr solitons have recently been generated in optical microresonators, enabling ultrashort optical pulses at microwave repetition rates, that constitute coherent and numerically predictable Kerr frequency combs. However, the seeding and excitation of the temporal solitons is associated with changes in the intracavity power, that can lead to large thermal resonance shifts during the excitation process and render the soliton states in most commonly used resonator platforms short lived. Here we describe a "power kicking" method to overcome this instability by modulating the power of the pump laser. A fast modulation triggers the soliton formation, while a slow adjustment of the power compensates the thermal effect during the excitation laser scan. With this method also initially very short-lived (100ns) soliton states , as encountered in SiN integrated photonic microresonators, can be brought into a steady state in contrast to techniques reported earlier which relied on an adjustment of the laser scan speed only. Once the soliton state is in a steady state it can persist for hours and is thermally self-locked.