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arXiv · 2503.14704

Scalable low loss cryogenic packaging of quantum memories in CMOS-foundry processed photonic chips

Robert Bernson·Alex Witte·Genevieve Clark·Kamil Gradkowski·Jeffrey Yang·Matt Saha·Matthew Zimmermann·Andrew Leenheer·Kevin Chen·Gerald Gilbert·Matt Eichenfield·Dirk Englund·Peter O'Brien
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Abstract

Optically linked solid-state quantum memories such as color centers in diamond are a promising platform for distributed quantum information processing and networking. Photonic integrated circuits (PICs) have emerged as a crucial enabling technology for these systems, integrating quantum memories with efficient electrical and optical interfaces in a compact and scalable platform. Packaging these hybrid chips into deployable modules while maintaining low optical loss and resiliency to temperature cycling is a central challenge to their practical use. We demonstrate a packaging method for PICs using surface grating couplers and angle-polished fiber arrays that is robust to temperature cycling, offers scalable channel count, applies to a wide variety of PIC platforms and wavelengths, and offers pathways to automated high-throughput packaging. Using this method, we show optically and electrically packaged quantum memory modules integrating all required qubit controls on chip, operating at millikelvin temperatures with < 3dB losses achievable from fiber to quantum memory.

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Robert Bernson, Alex Witte, Genevieve Clark, Kamil Gradkowski, Jeffrey Yang, Matt Saha, Matthew Zimmermann, Andrew Leenheer, Kevin Chen, Gerald Gilbert, Matt Eichenfield, Dirk Englund, Peter O'Brien. 2025-03-18. Scalable low loss cryogenic packaging of quantum memories in CMOS-foundry processed photonic chips. https://arxiv.org/abs/2503.14704

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