Coherence of optically addressable spin centers created in hexagonal boron nitride by proton irradiation

Abstract

Spin-carrying defects possessing optically addressable ground states in semiconductors allow the development of solid-state quantum technologies. Recently such type of defect has been found in hexagonal boron nitride (hBN) and identified as a negatively charged boron vacancy (VB-). Here we investigate the possibility to create VB- centers in hBN by irradiation with high-energy protons (EP=15 MeV), and probe the spin-coherence of the defects. Electron paramagnetic resonance methods show that such irradiation generates the VB-centers. Spin-relaxation times (T1 and T2) of VB- spin ensembles created by proton irradiation are determined to be 20 µs and 4 µs, respectively. PACS: 71.70.Ch, 75.10.Dg, 76.30.Kg, 71.70.Ej.