# Non-Hermitian engineering for brighter broadband pseudothermal light

## TL;DR

This paper demonstrates how non-Hermitian engineering, specifically spectral-loss engineering, can enhance broadband pseudothermal light generation, enabling new quantum light sources by leveraging nonlinear interactions and loss.

## Contribution

It introduces a novel approach of using loss engineering to relax phase-matching conditions, facilitating broadband pseudothermal state generation in semiconductor materials.

## Key findings

- Loss engineering relaxes phase-matching constraints
- Enables broadband pseudothermal light at new frequencies
- Potential for on-chip quantum light sources

## Abstract

We show that non-Hermitian engineering can play a positive role in quantum systems. This is in contrast to the widely accepted notion that optical losses are a foe that must be eliminated or, at least, minimized. We take advantage of the interplay between nonlinear interactions and loss to show that spectral-loss engineering can relax phase-matching conditions, enabling generation of broadband pseudothermal states at new frequencies. This opens the door for utilizing the full potential of semiconductor materials that exhibit giant nonlinearities but lack the necessary ingredients for achieving quasi-phase matching. This in turn may pave the way for building on-chip quantum light sources.