Reliable coherent optical memory based on a laser-written waveguide

Chao Liu, Zong-Quan Zhou, Tian-Xiang Zhu +10

${}^{151}\mathrm{E}{\mathrm{u}}^{3+}$-doped yttrium silicate (${}^{151}\mathrm{E}{\mathrm{u}}^{3+}:{\mathrm{Y}}_2\mathrm{Si}{\mathrm{O}}_5$ ) crystal is a unique material that possesses hyperfine states with coherence time up to 6 h. M…