# Photodynamics of quantum emitters in hexagonal boron nitride revealed by low temperature spectroscopy

## TL;DR

This study investigates the optical properties and photodynamics of quantum emitters in hexagonal boron nitride at cryogenic temperatures, revealing their coherence times and relaxation processes crucial for quantum information applications.

## Contribution

It provides detailed temperature-resolved photoluminescence and ultrafast spectral diffusion measurements of hBN quantum emitters, offering new insights into their relaxation dynamics.

## Key findings

- Photon coherence time of 81 ps measured
- Spectral diffusion partially explains coherence limitations
- Insights into relaxation processes in hBN emitters

## Abstract

Quantum emitters in hexagonal boron nitride (hBN) have recently emerged as promising bright single photon sources. In this letter we investigate in details their optical properties at cryogenic temperatures. In particular, we perform temperature resolved photoluminescence studies and measure photon coherence times from the hBN emitters. The obtained value of 81(1) ps translates to a width of $\sim$12 GHz which is higher than the Fourier transform limited value of $\sim$32 MHz. To account for the photodynamics of the emitter, we perform ultrafast spectral diffusion measurements that partially account for the coherence times. Our results provide important insight into the relaxation processes in quantum emitters in hBN which is mandatory to evaluate their applicability for quantum information processing.