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arXiv · 1910.14298

Optically unstable phase from ion-ion interactions in an erbium doped crystal

Yu-Hui Chen·Sebastian P. Horvath·Jevon J. Longdell·Xiangdong Zhang
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Abstract

We demonstrate an optical unstable phase for a laser driven erbium ion ensemble. The transmitted light through an erbium-doped yttrium orthosillicate crystal becomes dynamically unstable when illuminated by a strong continuous-wave laser. Transient net gain was recorded if the light passes the sample twice. The experimental results are understood in the framework of a many-body system interacting with a classical field, where the ion-ion interaction becomes significant as a result of the high erbium concentration. A Bloch-equation model that includes the excitation-induced frequency-shift is introduced to discuss the conditions of the instabilities.

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Yu-Hui Chen, Sebastian P. Horvath, Jevon J. Longdell, Xiangdong Zhang. 2019-10-31. Optically unstable phase from ion-ion interactions in an erbium doped crystal. https://doi.org/10.1103/physrevlett.126.110601

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