Studies of electron diffusion in photo-excited Ni using time-resolved X-ray diffraction

In this study, we investigated the electrondiffusion in a 150  nm thicknickelfilmdeposited on an indium antimonide substrate. A strain wave that mimics the heatdeposition profile is generated in the metal and propagates into theInSb, where it influences the temporal profile ofX-raysdiffracted fromInSb. We found that the strain pulse significantly deviated from a simple exponential profile, and that the two-temperaturemodel was needed to reproduce themeasured heatdeposition profile. Experimental results were compared to simulations based on the two-temperaturemodel carried out using commercial finite-element software packages and on-line dynamicaldiffraction tools. To reproduce the experimental data, the electron –phonon coupling factor was lowered compared to previouslymeasured values. The experiment was carried out at a third-generation synchrotron radiation source using a high-brightness beam and an ultrafastX-ray streak camera with a temporal resolution of 3 ps.

Source: Applied Physics Letters - November 18, 2016 Category: Physics Authors: A. I. H. Persson, A. Jarnac, Xiaocui Wang, H. Enquist, A. Jurgilaitis and J. Larsson Source Type: research