Single spin resonance in a van der Waals embedded paramagnetic defect

• Published in: arXiv.org
• Main Authors: Chejanovsky, Nathan, Mukherjee, Amlan, Kim, Youngwook, Denisenko, Andrej, Finkler, Amit, Taniguchi, Takashi, Watanabe, Kenji, Durga Bhaktavatsala Rao Dasari, Smet, Jurgen H, Wrachtrup, Jörg
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 13.06.2019
• Subjects: Boron nitride; Dependence; Magnetic resonance; Phonons; Photoluminescence; Physics - Mesoscale and Nanoscale Physics; Physics - Optics; Relaxation time; Spin resonance; Upper bounds
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1906.05903

Spins constitute a group of quantum objects forming a key resource in modern quantum technology. Two-dimensional (2D) van der Waals materials are of fundamental interest for studying nanoscale magnetic phenomena. However, isolating singular paramagnetic spins in 2D systems is challenging. We report here on a quantum emitting source embedded within hexgonal boron nitride (h-BN) exhibiting optical magnetic resonance (ODMR). We extract an isotropic \(g\) factor close to 2 and derive an upper bound for a zero field splitting (ZFS) (\(\leq\) 4 MHz). Photoluminescence (PL) behavior under temperature cycling using different excitations is presented, assigning probable zero phonon lines (ZPLs) / phonon side band (PSBs) to emission peaks, compatible with h-BN's phonon density of states, indicating their intrinsic nature. Narrow and inhomogeneous broadened ODMR lines differ significantly from monoatomic vacancy defect lines known in literature. We derive a hyperfine coupling of around 10 MHz. Its angular dependence indicates an unpaired electron in an out-of-plane \(\pi\)-orbital, probably originating from an additional substitutional carbon impurity or other low mass atom. We determine the spin relaxation time \(T_1\) to be around 17 \(\mu\)s.