Slow-light all-optical soliton diode based on tailored Bragg-grating structure

TL;DR

This paper proposes a novel all-optical soliton diode using a tailored Bragg-grating structure that achieves high nonreciprocal transmission and slow soliton propagation near the photonic bandgap.

Contribution

It introduces a new sandwich nonlinear Bragg-grating design for an all-optical soliton diode with enhanced nonreciprocity and slow light capabilities.

Findings

Transmission ratio up to 150 achieved.

Solitons propagate at velocities less than 0.03c.

High nonreciprocal transmission near photonic bandgap.

Abstract

An all optical soliton diode (AOSD) is proposed based on a sandwich nonlinear Bragg-grating structure: a linearly chirped Bragg-grating linked to a uniform Bragg-grating and again to a chirped Bragg-grating. The nonreciprocity is achieved by introducing two spatially asymmetric chirped Bragg-gratings with optical nonlinearity. High transmission ratio up to 150 is obtained when launching a picosecond Gaussian pulse into the setting. We find that such pulses in a form of solitons propagate at a rather small velocity ($<0.03c$) when pulse wavelength is selected in the vicinity of photonic bandgap.