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Title: Parallel single-shot measurement and coherent control of solid-state spins below the diffraction limit

Solid-state spin defects are a promising platform for quantum science and technology. The realization of larger-scale quantum systems with solid-state defects will require high-fidelity control over multiple defects with nanoscale separations, with strong spin-spin interactions for multi-qubit logic operations and the creation of entangled states. We demonstrate an optical frequency-domain multiplexing technique, allowing high-fidelity initialization and single-shot spin measurement of six rare-earth (Er3+) ions, within the subwavelength volume of a single, silicon photonic crystal cavity. We also demonstrate subwavelength control over coherent spin rotations by using an optical AC Stark shift. Our approach may be scaled to large numbers of ions with arbitrarily small separation and is a step toward realizing strongly interacting atomic defect ensembles with applications to quantum information processing and fundamental studies of many-body dynamics.

Authors:
 ;  ;  ;  ;  
Award ID(s):
1640959
Publication Date:
NSF-PAR ID:
10199807
Journal Name:
Science
Volume:
370
Issue:
6516
Page Range or eLocation-ID:
p. 592-595
ISSN:
0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)
Sponsoring Org:
National Science Foundation
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