Walk-off induced dissipative breathers and dissipative breather gas in microresonators

TL;DR

This paper investigates dissipative soliton breathers in optical microresonators with second-order nonlinearity, revealing the role of group velocity differences, the emergence of a breather gas, and a turbulence locking phenomenon at statistical equilibrium.

Contribution

It introduces the concept of dissipative breather gas and explores velocity locking phenomena in microresonators with second-harmonic generation.

Findings

Identification of group velocity difference as key to breather existence

Observation of dissipative breather gas with nearly elastic collisions

Discovery of turbulence locking at statistical stationarity

Abstract

Dissipative solitons in optical microcavities have attracted significant attention in recent years due to their direct association with the generation of optical frequency combs. Here, we address the problem of dissipative soliton breathers in a microresonator with second-order nonlinearity, operating at the exact phase-matching for efficient second-harmonic generation. We elucidate the vital role played by the group velocity difference between the first and second harmonic pulses for the breather existence. We report the dissipative breather gas phenomenon, when multiple breathers propagate randomly in the resonator and collide nearly elastically. Finally, when the breather gas reaches an out-of-equilibrium statistical stationarity, we show how the velocity locking between first and second harmonic is still preserved, naming such phenomena turbulence locking.