Greatly Enhanced Emission from Spin Defects in Hexagonal Boron Nitride Enabled by a Low-Loss Plasmonic Nanocavity

Xiaohui Xu; Abhishek B Solanki; Demid Sychev; Xingyu Gao; Samuel Peana; Aleksandr S Baburin; Karthik Pagadala; Zachariah O Martin; Sarah N Chowdhury; Yong P Chen; Takashi Taniguchi; Kenji Watanabe; Ilya A Rodionov; Alexander V Kildishev; Tongcang Li; Pramey Upadhyaya; Alexandra Boltasseva; Vladimir M Shalaev

doi:10.1021/acs.nanolett.2c03100

Greatly Enhanced Emission from Spin Defects in Hexagonal Boron Nitride Enabled by a Low-Loss Plasmonic Nanocavity

Nano Lett. 2023 Jan 11;23(1):25-33. doi: 10.1021/acs.nanolett.2c03100. Epub 2022 Nov 16.

Authors

Xiaohui Xu^{1

2}, Abhishek B Solanki^{2

3}, Demid Sychev^{2

3}, Xingyu Gao⁴, Samuel Peana^{2

3}, Aleksandr S Baburin^{5

6}, Karthik Pagadala^{2

3}, Zachariah O Martin^{2

3}, Sarah N Chowdhury^{2

3}, Yong P Chen^{2

3

4

7

8

9

10}, Takashi Taniguchi¹¹, Kenji Watanabe¹², Ilya A Rodionov^{5

6}, Alexander V Kildishev^{2

3

7}, Tongcang Li^{2

3

4

7}, Pramey Upadhyaya^{3

7

8}, Alexandra Boltasseva^{1

2

3

7

8}, Vladimir M Shalaev^{2

3

7

8}

Affiliations

¹ School of Materials Engineering, Purdue University, West Lafayette, Indiana47907, United States.
² Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana47907, United States.
³ Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana47907, United States.
⁴ Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana47907, United States.
⁵ FMN Laboratory, Bauman Moscow State Technical University, Moscow105005, Russia.
⁶ Dukhov Automatics Research Institute (VNIIA), Moscow127055, Russia.
⁷ Purdue Quantum Science and Engineering Institute (PQSEI), Purdue University, West Lafayette, Indiana47907, United States.
⁸ The Quantum Science Center (QSC), a National Quantum Information Science Research Center of the U.S. Department of Energy (DOE), Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States.
⁹ Institute of Physics and Astronomy and Villum Center for Hybrid Quantum Materials and Devices, Aarhus University, 8000Aarhus-C, Denmark.
¹⁰ WPI-AIMR International Research Center for Materials Sciences, Tohoku University, Sendai980-8577, Japan.
¹¹ International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan.
¹² Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba305-0044, Japan.

PMID: 36383034
DOI: 10.1021/acs.nanolett.2c03100

Abstract

The negatively charged boron vacancy (V_B^-) defect in hexagonal boron nitride (hBN) with optically addressable spin states has emerged due to its potential use in quantum sensing. Remarkably, V_B^- preserves its spin coherence when it is implanted at nanometer-scale distances from the hBN surface, potentially enabling ultrathin quantum sensors. However, its low quantum efficiency hinders its practical applications. Studies have reported improving the overall quantum efficiency of V_B^- defects with plasmonics; however, the overall enhancements of up to 17 times reported to date are relatively modest. Here, we demonstrate much higher emission enhancements of V_B^- with low-loss nanopatch antennas (NPAs). An overall intensity enhancement of up to 250 times is observed, corresponding to an actual emission enhancement of ∼1685 times by the NPA, along with preserved optically detected magnetic resonance contrast. Our results establish NPA-coupled V_B^- defects as high-resolution magnetic field sensors and provide a promising approach to obtaining single V_B^- defects.

Keywords: hBN; nanocavities; plasmonics; quantum sensing; spin defects; two-dimensional materials.