# Femtosecond Laser-Written Nanoablations Containing Bright Antibunched Emitters on Gallium Nitride

## TL;DR

Researchers used femtosecond lasers to create precise nanostructures on gallium nitride, enabling the controlled creation of quantum emitters with unique optical properties.

## Contribution

A deterministic method for fabricating bright, antibunched quantum emitters in ordered arrays on gallium nitride using femtosecond laser writing and annealing.

## Key findings

- Femtosecond laser-written nanoablations on GaN enabled sub-diffraction-limited patterning.
- Rapid thermal annealing activated stable, bright emitters with MHz antibunched emission.
- Emitters showed a sharp spectral peak at room temperature, indicating potential for quantum applications.

## Abstract

Femtosecond laser-writing
offers distinct capabilities for fabrication,
including three-dimensional, multimaterial, and sub-diffraction-limited
patterning. In particular, demonstrations of laser-written quantum
emitters and photonic devices with superior optical properties have
attracted attention. Recently, gallium nitride (GaN) has been reported
to host quantum emitters with narrow and bright zero-phonon photoluminescence
from ultraviolet to telecom ranges. However, emitters formed during
epitaxy are randomly positioned, and until now, it has not been possible
to fabricate quantum emitters in ordered arrays. In this paper, we
employ femtosecond laser writing to create nanoablations with sub-diffraction-limited
diameter and use rapid thermal annealing to activate co-located stable
emitters. The emitters show a MHz antibunched emission with a sharp
spectral peak at room temperature. Our study not only presents an
efficient approach to laser-written nanofabrication on GaN but also
offers a promising pathway for the deterministic creation of quantum
emitters in GaN, shedding light on the underlying mechanisms involved.