N. J. Hartley

N. J. Hartley

Research Associate

Using Diffuse Scattering to Observe X-Ray-Driven Nonthermal Melting

Published in Physical Review Letters, 2021

Recommended citation: N. J. Hartley et al. PRL 126.1 (2021) 015703. https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.126.015703

Using a high intensity (∼ 10^20 W/cm2) X-ray pump X-ray probe scheme, we observed changes in the ionic structure of silicon induced by X-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in incoherent scattering, which we attribute to a loss of lattice order and a transition to a liquid state within 100 fs of irradiation, a timescale which agrees well with first principles simulations. This method is capable of observing liquid scattering without masking or filtering of signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change. Recommended citation: N. J. Hartley et al. PRL 126.1 (2021) 015703.