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arXiv · 2008.12901

Coherent Optical Memory Baesd on A Laser-written On-chip Waveguide

Tian-Xiang Zhu·Chao Liu·Liang Zheng·Zong-Quan Zhou·Chuan-Feng Li·Guang-Can Guo
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Abstract

Quantum memory is the core device for the construction of large-scale quantum networks. For scalable and convenient practical applications, integrated optical memories, especially on-chip optical memories, are crucial requirements because they can be easily integrated with other on-chip devices. Here, we report the coherent optical memory based on a type-IV waveguide fabricated on the surface of a rare-earth ion-doped crystal (i.e. $\mathrm{Eu^{3+}}$:$\mathrm{Y_2SiO_5}$). The properties of the optical transition ($\mathrm{{^7}F{_0}\rightarrow{^5}D{_0}}$) of the $\mathrm{Eu^{3+}}$ ions inside the surface waveguide are well preserved compared to those of the bulk crystal. Spin-wave atomic frequency comb storage is demonstrated inside the type-IV waveguide. The reliability of this device is confirmed by the high interference visibility of ${97\pm 1\%}$ between the retrieval pulse and the reference pulse. The developed on-chip optical memory paves the way towards integrated quantum nodes.

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Tian-Xiang Zhu, Chao Liu, Liang Zheng, Zong-Quan Zhou, Chuan-Feng Li, Guang-Can Guo. 2020-12-04. Coherent Optical Memory Baesd on A Laser-written On-chip Waveguide. https://doi.org/10.1103/physrevapplied.14.054071

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