Robust Nuclear Spin Polarization via Ground-State Level Anticrossing of Boron Vacancy Defects in Hexagonal Boron Nitride

Nuclear spin polarization plays a crucial role in quantum information processing and quantum sensing. In this work, we demonstrate a robust and efficient method for nuclear spin polarization with boron vacancy (VB−) defects in hexagonal boron nitride (h-BN) using ground-state level anticrossing (GSLAC). We show that GSLAC-assisted nuclear polarization can be achieved with significantly lower laser power than excited-state level anticrossing, making the process experimentally more viable. Furthermore, we have demonstrated direct optical readout of nuclear spins for VB− in h-BN. Our findings suggest that GSLAC is a promising technique for the precise control and manipulation of nuclear spins in VB− defects in h-BN.Received 28 June 2023Revised 23 December 2023Accepted 30 May 2024DOI:https://doi.org/10.1103/PhysRevLett.132.266801© 2024 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasColor centersDefectsQuantum controlQuantum information processingSpin polarizationTechniquesOptically detected magnetic resonanceQuantum Information, Science & TechnologyCondensed Matter, Materials & Applied Physics