Selective lasing in multimode periodic and non-periodic nanopillar waveguides

TL;DR

This paper demonstrates selective lasing in multimode nanopillar waveguides with controllable supermodes, enabling switchable microlaser operation through coaxial seeding, offering an alternative to traditional external cavity tuning.

Contribution

It introduces a method for selective supermode lasing in nanopillar waveguides and proposes switchable lasing as a novel tuning mechanism.

Findings

Selective lasing into individual supermodes achieved.

Lasing wavelength can be controlled via coaxial seeding.

Proposed switchable lasing as an alternative tuning method.

Abstract

We investigate the lasing action in coupled multi-row nanopillar waveguides of periodic or fractal structure using the finite difference time domain (FDTD) method, coupled to the laser rate equations. Such devices exhibit band splitting with distinct and controllable supermode formation. We demonstrate that selective lasing into each of the supermodes is possible. The structure acts as a microlaser with selectable wavelength. Lasing mode selection is achieved by means of coaxial injection seeding with a Gaussian signal of appropriate transverse amplitude and phase profiles. Based on this we propose the concept of switchable lasing as an alternative to conventional laser tuning by means of external cavity control.