Quantum sensing with a spin ensemble in a two-dimensional material

Souvik Biswas; Giovanni Scuri; Noah Huffman; Eric I. Rosenthal; Ruotian Gong; Thomas Poirier; Xingyu Gao; Sumukh Vaidya; Abigail J. Stein; Tsachy Weissman; James H. Edgar; Tongcang Li; Chong Zu; Jelena Vučković; Joonhee Choi

arXiv · 2509.08984

Quantum sensing with a spin ensemble in a two-dimensional material

Souvik Biswas·Giovanni Scuri·Noah Huffman·Eric I. Rosenthal·Ruotian Gong·Thomas Poirier·Xingyu Gao·Sumukh Vaidya·Abigail J. Stein·Tsachy Weissman·James H. Edgar·Tongcang Li·Chong Zu·Jelena Vučković·Joonhee Choi

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Abstract

Quantum sensing with solid-state spin defects has transformed nanoscale metrology, offering sub-wavelength spatial resolution with exceptional sensitivity to multiple signal types. Maximizing these advantages requires minimizing both the sensor-target separation and the detectable signal threshold. However, leading platforms such as nitrogen-vacancy (NV) centers in diamond suffer from performance degradation near surfaces or in nanoscale volumes, motivating the search for optically addressable spin sensors in atomically thin, two-dimensional (2D) van der Waals materials. Here, we present a comprehensive experimental framework to probe a 2D spin ensemble, including its Hamiltonian, coherent sensing dynamics, and noise environment. Using a central spin system in a hexagonal boron nitride (hBN) crystal, we fully map the hyperfine interactions with proximal nuclear spins, demonstrate switchable magnetic and electric noise sensing, and introduce a method to accurately reconstruct the environmental noise spectrum while explicitly accounting for quantum control imperfections. We achieve a record coherence time of $80~\mu\mathrm{s}$ under dynamical decoupling, enabling sub-microtesla AC magnetic sensitivity at a $10~\mathrm{nm}$ target distance. Leveraging the broad opportunities for defect engineering in atomically thin hosts, these results lay the foundation for next-generation quantum sensors with ultrahigh sensitivity, tunable noise selectivity, and versatile functionalities.

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Souvik Biswas, Giovanni Scuri, Noah Huffman, Eric I. Rosenthal, Ruotian Gong, Thomas Poirier, Xingyu Gao, Sumukh Vaidya, Abigail J. Stein, Tsachy Weissman, James H. Edgar, Tongcang Li, Chong Zu, Jelena Vučković, Joonhee Choi. 2025-09-10. Quantum sensing with a spin ensemble in a two-dimensional material. https://arxiv.org/abs/2509.08984

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