Multi-wavelength Spin Dynamics of Defects in Hexagonal Boron Nitride

TL;DR

This study investigates how excitation wavelength influences the spin dynamics and fluorescence of defect spins in hexagonal boron nitride, revealing pathways to optimize quantum sensing performance.

Contribution

It uncovers the effects of excitation wavelength on spin-dependent fluorescence and dynamics in hBN defects, providing new insights for quantum technology applications.

Findings

Threefold increase in ODMR contrast with wavelength change

Strong impact of wavelength on photodynamics of spin emitters

Enhanced magnetic field sensitivity through wavelength tuning

Abstract

Optically addressable solid-state spin defects are essential platforms for quantum sensing and information processing. Recently, single spin defects with combined S = 1 and S = 1/2 spin transitions were discovered in hexagonal boron nitride (hBN). In this work we unveil their excitation dynamics. In particular, we study the effects of the excitation wavelength on the spin-dependent fluorescence and the spin dynamics of these peculiar quantum spin defects. We find that changing the excitation wavelength leads to a threefold enhancement in both the optically detected magnetic resonance (ODMR) contrast and the corresponding magnetic field sensitivity. In addition, we find that the excitation wavelength has a strong impact on the photodynamics of spin complex emitters. Our work presents valuable insights to the mechanistic understanding of spin complex emitters in hBN and highlights the importance of excitation wavelength for optimising their performance in quantum sensing and quantum technologies.