A continuum of bright and dark pulse states in a photonic-crystal resonator

TL;DR

This paper demonstrates a photonic-crystal resonator that supports a continuum of dark and bright pulse states, revealing new insights into the interplay of nonlinearity and normal GVD in nanophotonics.

Contribution

It introduces a resonator with unconditionally normal GVD supporting both dark and bright states, enabling exploration of a pulse continuum in a gapped nanophotonic medium.

Findings

Supports both dark and bright pulse states in a single device

Achieves highly designable, low-noise frequency combs

Reveals physical roles of Kerr nonlinearity and GVD in nanophotonics

Abstract

Nonlinearity is a powerful determinant of physical systems. Controlling nonlinearity leads to interesting states of matter and new applications. In optics, diverse families of continuous and discrete states arise from balance of nonlinearity and group-velocity dispersion (GVD). Moreover, the dichotomy of states with locally enhanced or diminished field intensity depends critically on the relative sign of nonlinearity and either anomalous or normal GVD. Here, we introduce a resonator with unconditionally normal GVD and a single defect mode that supports both dark, reduced-intensity states and bright, enhanced-intensity states. We access and explore this dark-to-bright pulse continuum by phase-matching for soliton generation with a photonic-crystal resonator, which mediates the competition of nonlinearity and normal GVD. These stationary temporal states are coherent frequency combs, featuring highly designable spectra and ultralow noise repetition-frequency and intensity characteristics. The dark-to-bright continuum illuminates physical roles of Kerr nonlinearity, GVD, and laser propagation in a gapped nanophotonic medium.