Spin defects in hBN as promising temperature, pressure and magnetic field quantum sensors

Andreas Gottscholl,Carlo Bradac,Igor Aharonovich,Igor Aharonovich,Andreas Sperlich,Mehran Kianinia,Mehran Kianinia,Dominik Krauße,Vladimir Dyakonov,Christian Kasper,Victor Soltamov,Victor Soltamov,Matthias Diez

doi:10.1038/s41467-021-24725-1

Abstract

Spin defects in solid-state materials are strong candidate systems for quantum information technology and sensing applications. Here we explore in details the recently discovered negatively charged boron vacancies (VB−) in hexagonal boron nitride (hBN) and demonstrate their use as atomic scale sensors for temperature, magnetic fields and externally applied pressure. These applications are possible due to the high-spin triplet ground state and bright spin-dependent photoluminescence of the VB−. Specifically, we find that the frequency shift in optically detected magnetic resonance measurements is not only sensitive to static magnetic fields, but also to temperature and pressure changes which we relate to crystal lattice parameters. We show that spin-rich hBN films are potentially applicable as intrinsic sensors in heterostructures made of functionalized 2D materials.

Highlights

Spin defects in solid-state materials are strong candidate systems for quantum information technology and sensing applications
The results presented in this work were obtained on single-crystal hexagonal boron nitride (hBN)
This crystallographic feature can be used to monitor local temperature variations optically, via optically detected magnetic resonance (ODMR), since the temperature-driven compression/expansion of the lattice parameters a and c causes a direct change in the zero-field splitting (ZFS) parameter Dgs of the triplet ground state[25]

Summary

Introduction

Spin defects in solid-state materials are strong candidate systems for quantum information technology and sensing applications. We explore in details the recently discovered negatively charged boron vacancies (VB−) in hexagonal boron nitride (hBN) and demonstrate their use as atomic scale sensors for temperature, magnetic fields and externally applied pressure. These applications are possible due to the high-spin triplet ground state and bright spin-dependent photoluminescence of the VB−. Center in diamond[1] and various types of spin defects in silicon carbide (SiC) (divacancy and silicon-vacancy)[2,3] These systems reveal optically detected magnetic resonance (ODMR), which allows for polarization, manipulation, and optical readout of their spin state and consequent mapping of external stimuli (magnetic/ electric field, temperature, pressure, etc.) onto it[4,5,6]. Our experiments show that the resolution and range of operation of the hBN VÀB center is competitive or exceeding those of similar defect-based sensors[23]

Methods

Results

Conclusion