Optical Spin Initialization of Nitrogen Vacancy Centers in a 28Si-Enriched 6H-SiC Crystal for Quantum Technologies

TL;DR

This study demonstrates optical spin initialization of nitrogen-vacancy centers in 28Si-enriched 6H-SiC crystals, revealing their spectroscopic properties and long relaxation times, which are promising for quantum technology applications.

Contribution

It provides the first detailed spectroscopic analysis of NV centers in 28Si-enriched 6H-SiC, including identification of three nonequivalent types and measurement of their relaxation times.

Findings

Identified three types of NV centers with axial symmetry.

Measured long spin-lattice (1.3 ms) and spin-spin (59 μs) relaxation times.

Achieved highly selective excitation of NV centers for quantum manipulation.

Abstract

High-spin defect centers in crystal matrices are used in quantum computing technologies, highly sensitive sensors, and single-photon sources. In this work, optically active nitrogen-vacancy color centers NV in a 28Si-enriched (nuclear spin I = 0) 6H-28SiC crystal have been studied using the photoinduced (980 nm) high-frequency (94 GHz, 3.4 T) pulsed electron paramagnetic resonance method at a temperature of 150 K. Three structurally nonequivalent types of NV- centers with axial symmetry have been identified and their spectroscopic parameters have been determined. Long spin-lattice, T1=1.3 ms, and spin-spin, T2=59 us, ensemble relaxation times of NV- centers with extremely narrow (450 kHz) absorption lines allow highly selective excitation of resonant transitions between sublevels caused by the weak hyperfine interaction (A = 1 MHz) with 14N (I = 1) nuclei for the quantum manipulation of the electron spin magnetization.