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arXiv · 2306.15207

Efficient Photonic Integration of Diamond Color Centers and Thin-Film Lithium Niobate

Abstract

On-chip photonic quantum circuits with integrated quantum memories have the potential to radically progress hardware for quantum information processing. In particular, negatively charged group-IV color centers in diamond are promising candidates for quantum memories, as they combine long storage times with excellent optical emission properties and an optically-addressable spin state. However, as a material, diamond lacks many functionalities needed to realize scalable quantum systems. Thin-film lithium niobate (TFLN), in contrast, offers a number of useful photonic nonlinearities, including the electro-optic effect, piezoelectricity, and capabilities for periodically-poled quasi-phase matching. Here, we present highly efficient heterogeneous integration of diamond nanobeams containing negatively charged silicon-vacancy (SiV) centers with TFLN waveguides. We observe greater than 90\% transmission efficiency between the diamond nanobeam and TFLN waveguide on average across multiple measurements. By comparing saturation signal levels between confocal and integrated collection, we determine a $10$-fold increase in photon counts channeled into TFLN waveguides versus that into out-of-plane collection channels. Our results constitute a key step for creating scalable integrated quantum photonic circuits that leverage the advantages of both diamond and TFLN materials.

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Daniel Riedel, Hope Lee, Jason F. Herrmann, Jakob Grzesik, Vahid Ansari, Jean-Michel Borit, Hubert S. Stokowski, Shahriar Aghaeimeibodi, Haiyu Lu, Patrick J. McQuade, Nick A. Melosh, Zhi-Xun Shen, Amir H. Safavi-Naeini, Jelena Vučković. 2023-06-27. Efficient Photonic Integration of Diamond Color Centers and Thin-Film Lithium Niobate. https://arxiv.org/abs/2306.15207

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