Coupling Spin Defects in a Layered Material to Nanoscale Plasmonic Cavities

Noah Mendelson; Ritika Ritika; Mehran Kianinia; John Scott; Sejeong Kim; Johannes E Fröch; Camilla Gazzana; Mika Westerhausen; Licheng Xiao; Seyed Sepehr Mohajerani; Stefan Strauf; Milos Toth; Igor Aharonovich; Zai-Quan Xu

doi:10.1002/adma.202106046

Coupling Spin Defects in a Layered Material to Nanoscale Plasmonic Cavities

Adv Mater. 2022 Jan;34(1):e2106046. doi: 10.1002/adma.202106046. Epub 2021 Oct 19.

Authors

Noah Mendelson¹, Ritika Ritika¹, Mehran Kianinia^{1

2}, John Scott^{1

2}, Sejeong Kim³, Johannes E Fröch¹, Camilla Gazzana¹, Mika Westerhausen¹, Licheng Xiao^{4

5}, Seyed Sepehr Mohajerani^{4

5}, Stefan Strauf^{4

5}, Milos Toth^{1

2}, Igor Aharonovich^{1

2}, Zai-Quan Xu¹

Affiliations

¹ School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales, 2007, Australia.
² ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), University of Technology Sydney, Ultimo, New South Wales, 2007, Australia.
³ Department of Electrical and Electronic Engineering, University of Melbourne, Victoria, 3010, Australia.
⁴ Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
⁵ Center for Quantum Science and Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.

PMID: 34601757
DOI: 10.1002/adma.202106046

Abstract

Spin defects in hexagonal boron nitride, and specifically the negatively charged boron vacancy (V_B ^- ) centers, are emerging candidates for quantum sensing. However, the V_B ^- defects suffer from low quantum efficiency and, as a result, exhibit weak photoluminescence. In this work, a scalable approach is demonstrated to dramatically enhance the V_B ^- emission by coupling to a plasmonic gap cavity. The plasmonic cavity is composed of a flat gold surface and a silver cube, with few-layer hBN flakes positioned in between. Employing these plasmonic cavities, two orders of magnitude are extracted in photoluminescence enhancement associated with a corresponding twofold enhancement in optically detected magnetic resonance contrast. The work will be pivotal to progress in quantum sensing employing 2D materials, and in realization of nanophotonic devices with spin defects in hexagonal boron nitride.

Keywords: cavity; hexagonal boron nitride; plasmonics; spin defects.

Abstract

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