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arXiv · 2510.07032

Modular interface for efficient optical readout of diamond quantum memory at cryogenic temperatures via single-mode optical fibers

Akira Kamimaki·Yuhei Sekiguchi·Daisuke Ito·Taichi Fujiwara·Toshiharu Makino·Hiromitsu Kato·Hideo Kosaka
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Abstract

Efficient quantum devices across various physical systems have been rapidly developed for entanglement-based quantum repeaters and spin-photon conversion; however, far less attention has been paid to standardizing platforms through quantum memory optical interfaces. We present a modular interface for color centers in diamond that is structurally isolated from device-and temperature-related variation. Despite a more than 100-fold reduction in confocal volume, we achieve highly efficient photon collection through single-mode optical fibers, including zero-phonon line spectroscopy, at both room and cryogenic temperatures. These results establish a standardized minimal NV-center-based platform and pave the way for construction of scalable quantum infrastructure.

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Akira Kamimaki, Yuhei Sekiguchi, Daisuke Ito, Taichi Fujiwara, Toshiharu Makino, Hiromitsu Kato, Hideo Kosaka. 2025-10-08. Modular interface for efficient optical readout of diamond quantum memory at cryogenic temperatures via single-mode optical fibers. https://arxiv.org/abs/2510.07032

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