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arXiv · 2405.16303

Extended spin relaxation times of optically addressed telecom defects in silicon carbide

Jonghoon Ahn·Christina Wicker·Nolan Bitner·Michael T. Solomon·Benedikt Tissot·Guido Burkard·Alan M. Dibos·Jiefei Zhang·F. Joseph Heremans·David D. Awschalom
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Abstract

Optically interfaced solid-state defects are promising candidates for quantum communication technologies. The ideal defect system would feature bright telecom emission, long-lived spin states, and a scalable material platform, simultaneously. Here, we employ one such system, vanadium (V4+) in silicon carbide (SiC), to establish a potential telecom spin-photon interface within a mature semiconductor host. This demonstration of efficient optical spin polarization and readout facilitates all optical measurements of temperature-dependent spin relaxation times (T1). With this technique, we lower the temperature from about 2K to 100 mK to observe a remarkable four-orders-of-magnitude increase in spin T1 from all measured sites, with site-specific values ranging from 57 ms to above 27 s. Furthermore, we identify the underlying relaxation mechanisms, which involve a two-phonon Orbach process, indicating the opportunity for strain-tuning to enable qubit operation at higher temperatures. These results position V4+ in SiC as a prime candidate for scalable quantum nodes in future quantum networks.

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Jonghoon Ahn, Christina Wicker, Nolan Bitner, Michael T. Solomon, Benedikt Tissot, Guido Burkard, Alan M. Dibos, Jiefei Zhang, F. Joseph Heremans, David D. Awschalom. 2024-05-25. Extended spin relaxation times of optically addressed telecom defects in silicon carbide. https://arxiv.org/abs/2405.16303

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