Demonstration of a self-pulsing photonic crystal Fano laser

TL;DR

This paper introduces a novel ultra-small photonic crystal laser utilizing a Fano resonance mirror, enabling single-mode operation and self-pulsing behavior at gigahertz frequencies, with potential applications in integrated photonics.

Contribution

The work demonstrates a self-pulsing photonic crystal Fano laser using a Fano resonance mirror, a novel approach that enables ultracompact size, single-mode operation, and gigahertz pulse generation.

Findings

Laser exhibits self-pulsing at gigahertz frequencies.

Fano resonance enables narrow-band, single-mode laser operation.

Nonlinearities in the Fano mirror promote pulse generation.

Abstract

Semiconductor lasers in use today rely on mirrors based on the reflection at a cleaved facet or Bragg reflection from a periodic stack of layers. Here, we demonstrate an ultra-small laser with a mirror based on the Fano resonance between a continuum of waveguide modes and the discrete resonance of a nanocavity. The Fano resonance leads to unique laser characteristics. Since the Fano mirror is very narrow-band compared to conventional lasers, the laser is single-mode and in particular, it can be modulated via the mirror. We show, experimentally and theoretically, that nonlinearities in the mirror may even promote the generation of a self-sustained train of pulses at gigahertz frequencies, an effect that was previously only observed in macroscopic lasers. Such a source is of interest for a number of applications within integrated photonics.