Understanding Decoherence of the Boron Vacancy Center in Hexagonal Boron Nitride

Abstract

Hexagonal boron nitride (hBN) has emerged as a significant material for quantum sensing, particularly due to its ability to host spin active defects, such as the negatively charged boron vacancy (V${}_{\mathrm{B}}^{-}$ center). The optical addressability of the V${}_{\mathrm{B}}^{-}$ center and hBN's 2D structure enable high spatial resolution and integration into various platforms. However, decoherence due to the strong magnetic noise in hBN imposes fundamental limitations on the sensitivity of V${}_{\mathrm{B}}^{-}$ center-based applications. Understanding the phenomena behind decoherence and identifying parameter settings that provide the highest performance are essential for advancing V${}_{\mathrm{B}}^{-}$ sensors. This study employs state-of-the-art computational methods to investigate the decoherence of the V${}_{\mathrm{B}}^{-}$ center in hexagonal boron nitride across a wide range of magnetic field values from 0 T up to 3 T. The provided in-depth numerical and analytical analysis reveals an intricate interplay of various decoherence mechanisms. This study identifies five distinct magnetic field regions governed by different types of magnetic interactions with and within the abundant nuclear spin bath. In addition to magnetic field, the effects of zero-field splitting, nuclear polarization, and different hyperfine coupling terms are studied, representing an important step forward in utilizing V${}_{\mathrm{B}}^{-}$ ensembles in sensing. In particular, this study proposes operation in the moderate $180-350$ mT magnetic field range in chemically pure h${}^{11}$B${}^{15}$N samples, where the coherence time can reach $1-20$ $\mu$s, significantly exceeding the $\mathcal{O}(100\text{ns})$ low-field $T_2$ values.

References in corpus (20)

• Quantum sensing with arbitrary frequency resolution
• Sub-nanoscale Temperature, Magnetic Field and Pressure sensing with Spin Centers in 2D hexagonal Boron Nitride
• Quantum many-body theory of qubit decoherence in a finite-size spin bath
• Pure quantum dephasing of a solid state electron spin qubit in a large nuclear spin bath coupled by long-range hyperfine-mediated interactions
• Quantum many-body theory for electron spin decoherence in nanoscale nuclear spin baths
• Wide Field Imaging of van der Waals Ferromagnet Fe3GeTe2 by Spin Defects in Hexagonal Boron Nitride
• Single-molecule Scale Magnetic Resonance Spectroscopy using Nitrogen-Vacancy Centers in Diamond
• Electron Spin Decoherence in Silicon Carbide Nuclear Spin Bath
• Room temperature coherent control of protected qubit in hexagonal boron nitride
• Nanodiamond quantum sensors reveal temperature variation associated to hippocampal neurons firing
• Magnetic imaging with spin defects in hexagonal boron nitride
• Coherent dynamics of multi-spin ${\mathrm{V}}_{\mathrm{B}}^{-}$ centers in hexagonal boron nitride
• Optically-active spin defects in few-layer thick hexagonal boron nitride
• Electron-nuclear coherent coupling and nuclear spin readout through optically polarized VB- spin states in hBN
• Isotope engineering for spin defects in van der Waals materials
• Isotopic control of the boron-vacancy spin defect in hexagonal boron nitride
• Detection of paramagnetic spins with an ultrathin van der Waals quantum sensor
• Quantum sensing of paramagnetic spins in liquids with spin qubits in hexagonal boron nitride
• Magnetic-field dependent VB- spin decoherence in hexagonal boron nitrides: A first-principles study
• First-principles computational methods for quantum defects in two-dimensional materials: A perspective

Cited by in corpus (2)

• Nuclear Spin-Mediated Relaxation Mechanisms of the V${}_B^{-}$ Center in hBN
• Identifying optimal magnetic field configurations for decoherence mitigation of boron vacancies in hexagonal boron nitride