Wavelength switching dynamics of two-colour semiconductor lasers with optical injection and feedback

TL;DR

This paper investigates the wavelength switching behavior of two-colour semiconductor lasers with optical injection and feedback, demonstrating bistability and potential for fast optical memory applications through experiments and simulations.

Contribution

It introduces a novel two-colour laser design with etched slotted regions and explores their wavelength switching dynamics under optical injection and feedback, supported by experimental and numerical analysis.

Findings

Optical injection induces wavelength bistability in two-colour lasers.

Time-delayed optical feedback can also induce wavelength bistability.

The system can function as a fast optical memory device.

Abstract

The wavelength switching dynamics of two-colour semiconductor lasers with optical injection and feedback are presented. These devices incorporate slotted regions etched into the laser ridge waveguide for tailoring the output spectrum. Experimental measurements are presented demonstrating that optical injection in one or both modes of these devices can induce wavelength bistability. Measured switching dynamics with modulated optical injection are shown to be in excellent agreement with numerical simulations based on a simple rate equation model. We also demonstrate experimentally that time-delayed optical feedback can induce wavelength bistability for short external cavity lengths. Numerical simulations indicate that this two-colour optical feedback system can provide fast optical memory functionality based on injected optical pulses without the need for an external holding beam.