Synergistic ion beam engineering of high-performance spin–photon interfaces in hexagonal boron nitride

Y Yun-Tao Wu (State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,) X Xu Guo P Peng-Tao Jing (State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,) Z Zhen Cheng (State Key Laboratory of Drug Research, Molecular Imaging Center) J Ji-Lian Xu (State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,) H Hai Xu (Department of Biological and Energy Chemical Engineering, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China) L Li-Gong Zhang (State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,) D Da Zhan (State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,) J Jia-Xu Yan (State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,) Y Yang Bao H Hai Zhu L Lei Liu D De-Zhen Shen (State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,)

Abstract

Deterministically coupling spin defects to optical microcavities is critical for scalable quantum sensing yet remains a fabrication bottleneck. Here, we demonstrate the deterministic integration of negatively charged boron vacancy (VB−) spin defects in hexagonal boron nitride (h-BN) with circular Bragg grating microcavities using a dual-beam focused ion beam approach. While standard heavy-ion lithography often degrades emitter quality through lattice amorphization, we demonstrate that helium ion (He+) irradiation enables the surgical creation of VB− centers with preserved long-range crystalline order. By combining Ga+ ions milling for cavity definition with in situ He+ ion writing, we achieve sub-15 nm spatial alignment between the emitter and the cavity mode volume, eliminating registration errors inherent to overlay lithography. The fabricated device exhibits highly directional emission with a Purcell factor of 1.57, evidenced by a reduction in fluorescence lifetime. These photonic enhancements translate to high-fidelity capabilities in optically detected magnetic resonance spin readout, establishing this monolithic fabrication strategy as a robust pathway for scalable, high-sensitivity quantum sensing arrays.

Article Details

Volume / Issue Vol. 128, Issue 14
Published April 06, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (13)

Y

Yun-Tao Wu

State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,

X

Xu Guo

P

Peng-Tao Jing

State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,

Z

Zhen Cheng

State Key Laboratory of Drug Research, Molecular Imaging Center

J

Ji-Lian Xu

State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,

H

Hai Xu

Department of Biological and Energy Chemical Engineering, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao 266580, China

L

Li-Gong Zhang

State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,

D

Da Zhan

State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,

J

Jia-Xu Yan

State Key Laboratory of Luminescence Science and Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences 1 , No. 3888 Dongnanhu Road, Changchun 130033,

Y

Yang Bao

H

Hai Zhu

L

Lei Liu

D

De-Zhen Shen

State Key Laboratory of Opto-Electronic Information Acquisition and Protection Technology, Anhui University 3 , Hefei 230601,