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arXiv · 2309.02308

BGO relaxation dynamics probed with heterodyne detected optical transient gratings

Danny Fainozzi·Sara Catalini·Renato torre·Claudio Masciovecchio·Cristian Svetina
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Abstract

We used optical laser pulses to create transient gratings (TGs) with sub-10 {\mu}m spatial periodicity in a Bismuth Germanate (310) (Bi4Ge3O12) single crystal at room temperature. The TG launches phonon modes, whose dynamics were revealed via forward diffraction of a third, time-delayed, heterodyne-detected optical pulse. Acoustic oscillations have been clearly identified in a time-frequency window not covered by previous spectroscopic studies and their characteristic dynamic parameters have been measured as a function of transferred momenta magnitude and direction.

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Danny Fainozzi, Sara Catalini, Renato torre, Claudio Masciovecchio, Cristian Svetina. 2023-09-05. BGO relaxation dynamics probed with heterodyne detected optical transient gratings. https://arxiv.org/abs/2309.02308

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