Integrating solid-state quantum emitters with photonic circuits
is essential for realizing large-scale quantum photonic processors. Negatively
charged tin-vacancy (SnV−) centers in diamond have emerged as promising
candidates for quantum emitters because of their excellent optical and spin
properties, including narrow-linewidth emission and long spin coherence times.
SnV− centers need to be incorporated in optical waveguides for efficient onchip
routing of the photons they generate. However, such integration has yet to
be realized. In this Letter, we demonstrate the coupling of SnV− centers to a
nanophotonic waveguide. We realize this device by leveraging our recently
developed shallow ion implantation and growth method for the generation of
high-quality SnV− centers and the advanced quasi-isotropic diamond
fabrication technique. We confirm the compatibility and robustness of these
techniques through successful coupling of narrow-linewidth SnV− centers (as
narrow as 36 ± 2 MHz) to the diamond waveguide. Furthermore, we investigate the stability of waveguide-coupled SnV− centers
under resonant excitation. Our results are an important step toward SnV−-based on-chip spin-photon interfaces, single-photon
nonlinearity, and photon-mediated spin interactions.
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This content will become publicly available on November 1, 2024
Microwave-Based Quantum Control and Coherence Protection of Tin-Vacancy Spin Qubits in a Strain-Tuned Diamond-Membrane Heterostructure
Robust spin-photon interfaces in solids are essential components in quantum networking and sensing technologies. Ideally, these interfaces combine a long-lived spin memory, coherent optical transitions, fast and high-fidelity spin manipulation, and straightforward device integration and scaling. The tin-vacancy center (SnV) in diamond is a promising spin-photon interface with desirable optical and spin properties at 1.7 K. However, the SnV spin lacks efficient microwave control, and its spin coherence degrades with higher temperature. In this work, we introduce a new platform that overcomes these challenges—SnV centers in uniformly strained thin diamond membranes. The controlled generation of crystal strain introduces orbital mixing that allows microwave control of the spin state with 99.36(9)% gate fidelity and spin coherence protection beyond a millisecond. Moreover, the presence of crystal strain suppresses temperature-dependent dephasing processes, leading to a considerable improvement of the coherence time up to 223(10) μs at 4 K, a widely accessible temperature in common cryogenic systems. Critically, the coherence of optical transitions is unaffected by the elevated temperature, exhibiting nearly lifetime-limited optical linewidths. Combined with the compatibility of diamond membranes with device integration, the demonstrated platform is an ideal spin-photon interface for future quantum technologies.
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- Award ID(s):
- 2240399
- NSF-PAR ID:
- 10482893
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review X
- Volume:
- 13
- Issue:
- 4
- ISSN:
- 2160-3308
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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