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

Journal Article · Fri Aug 21 00:00:00 EDT 2020 · Physical Review Letters

OSTI ID:1656754

Hartley, Nicholas J. ^[1]; Grenzer, J. ^[2]; Huang, L. ^[2]; Inubushi, Y. ^[3]; Kamimura, N. ^[4]; Katagiri, K. ^[4]; Kodama, R. ^[4]; Kon, A. ^[3]; Lu, W. ^[5]; Makita, M. ^[5]; Matsuoka, T. ^[4]; Nakajima, S. ^[4]; Ozaki, N. ^[4]; Pikuz, T. ^[4]; Rode, A. ^[6]; Sagae, D. ^[4]; Schuster, A. K. ^[2]; Tono, K. ^[3]; Voigt, K. ^[2]; Vorberger, J. ^[2] ; Yabuuchi, T. ^[3]; McBride, E. E. ^[7]; Kraus, D. ^[2]

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1. SLAC National Accelerator Lab., Menlo Park, CA (United States); Helmholtz-Zentrum Dresden Rossendorf, (Germany)
2. Helmholtz-Zentrum Dresden Rossendorf, (Germany)
3. Japan Synchrotron Radiation Research Inst., Sayo, Hyogo (Japan); RIKEN, Sayo, Hyogo (Japan)
4. Osaka Univ., Suita (Japan)
5. European X-ray Free-Electron Laser (XFEL), Schenefeld (Germany)
6. Australian National Univ., Canberra, ACT (Australia)
7. SLAC National Accelerator Lab., Menlo Park, CA (United States)

We present results from the SPring-8 Angstrom Compact free electron LAser (SACLA) XFEL facility, using a high intensity ($$\sim\!10^{20}\,$$W/cm$^2$) X-ray pump X-ray probe scheme to observe 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 diffuse 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, but is faster than that predicted by purely inertial behavior. 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.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC); Japan Synchrotron Radiation Research Inst. (JASRI); Japan Society for the Promotion of Science (JSPS); Helmholtz Association; Australian Research Council
• Contributing Organization: High Energy Density Science
• DOE Contract Number: AC02-76SF00515; 2017B8075; 2018A8056; 16K17846; VH-NG-1141; DP170100131
• OSTI ID: 1656754
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters
• Country of Publication: United States
• Language: English