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arXiv · 1206.1097

Dynamics of colloidal crystals studied by pump-probe experiments at FLASH

R. Dronyak·J. Gulden·O. M. Yefanov·A. Singer·T. Gorniak·T. Senkbeil·J. -M. Meijer·A. Al-Shemmary·J. Hallmann·D. D. Mai·T. Reusch·D. Dzhigaev·R. P. Kurta·U. Lorenz·A. V. Petukhov·S. Duesterer·R. Treusch·M. N. Strikhanov·E. Weckert·A. P. Mancuso·T. Salditt·A. Rosenhahn·I. A. Vartanyants
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Abstract

We present a time-resolved infrared (IR) pump and extreme-ultraviolet (XUV) probe diffraction experiment to investigate ultrafast structural dynamics in colloidal crystals with picosecond resolution. The experiment was performed at the FLASH facility at DESY with a fundamental wavelength of 8 nm. In our experiment, the temporal changes of Bragg peaks were analyzed and their frequency components were calculated using Fourier analysis. Periodic modulations in the colloidal crystal were localized at a frequency of about 4-5 GHz. Based on the Lamb theory, theoretical calculations of vibrations of the isotropic elastic polystyrene spheres of 400 nm in size reveal a 5.07 GHz eigenfrequency of the ground (breathing) mode.

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R. Dronyak, J. Gulden, O. M. Yefanov, A. Singer, T. Gorniak, T. Senkbeil, J. -M. Meijer, A. Al-Shemmary, J. Hallmann, D. D. Mai, T. Reusch, D. Dzhigaev, R. P. Kurta, U. Lorenz, A. V. Petukhov, S. Duesterer, R. Treusch, M. N. Strikhanov, E. Weckert, A. P. Mancuso, T. Salditt, A. Rosenhahn, I. A. Vartanyants. 2012-06-06. Dynamics of colloidal crystals studied by pump-probe experiments at FLASH. https://doi.org/10.1103/physrevb.86.064303

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