# Photonic Flatband Laser

## TL;DR

This paper demonstrates that flatband photonic lattices can support stable, cooperative laser emission through selective pumping, enabling new possibilities for light trapping and imaging with flatland structures.

## Contribution

It introduces the concept of flatband lasing in photonic lattices, showing stable laser emission in a system with degenerate supermodes using selective pumping.

## Key findings

- Stable flatband laser emission achieved
- Selective pumping induces cooperative lasing
- Potential for advanced light trapping and imaging

## Abstract

Flatband photonic lattices, i.e. arrays of waveguides or resonators displaying a flat Bloch band, offer new routes for light trapping and distortion-free imaging. Here it is shown that flatland lattices can show stable and cooperative laser emission when optical gain is supplied to the system, despite the large degree of degeneracy of flatland supermodes. By considering a quasi one-dimensional rhombic lattice of coupled semiconductor microrings, selective pumping of the outer sublattices can induce cooperative lasing in a supermode of the flat band