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arXiv · 2403.07850

Laser-written waveguide-integrated coherent spins in diamond

Yanzhao Guo·John P. Hadden·Federico Gorrini·Giulio Coccia·Vibhav Bharadwaj·Vinaya Kumar Kavatamane·Mohammad Sahnawaz Alam·Roberta Ramponi·Paul E. Barclay·Andrea Chiappini·Maurizio Ferrari·Alexander Kubanek·Angelo Bifone·Shane M. Eaton·Anthony J. Bennett
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Abstract

Quantum emitters, such as the negatively charged nitrogen-vacancy center in diamond, are attractive for quantum technologies such as nano-sensing, quantum information processing, and as a non-classical light source. However, it is still challenging to position individual emitters in photonic structures whilst preserving the spin coherence properties of the defect. In this paper, we investigate single and ensemble waveguide-integrated nitrogen-vacancy centers in diamond fabricated by femtosecond laser writing followed by thermal annealing. Their spin coherence properties are systematically investigated and are shown to be comparable to native nitrogen-vacancy centers in diamond. This method paves the way for the fabrication of coherent spins integrated within photonic devices.

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Yanzhao Guo, John P. Hadden, Federico Gorrini, Giulio Coccia, Vibhav Bharadwaj, Vinaya Kumar Kavatamane, Mohammad Sahnawaz Alam, Roberta Ramponi, Paul E. Barclay, Andrea Chiappini, Maurizio Ferrari, Alexander Kubanek, Angelo Bifone, Shane M. Eaton, Anthony J. Bennett. 2024-03-12. Laser-written waveguide-integrated coherent spins in diamond. https://doi.org/10.1063/5.0209294

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