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arXiv · 2210.06243

Pump-probe Dark-field X-ray Microscopy

Ishwor Poudyal·Zhi Qiao·Arndt Last·Michael R. Armstrong·Zahir Islam
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Abstract

A pump-probe dark-field X-ray microscopy (DFXM) experiment was carried out at the Advanced Photon Source (APS) with nanosecond drive laser pulses and hybrid mode X-ray probe pulses. We observe a thermal decay due to laser-induced heat diffusion in a Germanium single crystal which matches the theoretical prediction. The single pulse DFXM imaging in combination with the laser-pump X-ray probe method could reveal thermal strain formation and propagation of the acoustic wave "on-the-fly" generated by a laser-induced lattice deformation. This will open a new avenue of materials research on laser-induced dynamic phenomena in solids at sub-nanosecond time scales.

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Ishwor Poudyal, Zhi Qiao, Arndt Last, Michael R. Armstrong, Zahir Islam. 2022-10-12. Pump-probe Dark-field X-ray Microscopy. https://arxiv.org/abs/2210.06243

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