Ultrafast x-ray studies of laser-driven non-equilibrium dynamics in network-modified silicate glasses

Silicate glasses are widely used in scientific and industrial applications, where they are often subjected to high-energy ballistics, impact, and thermal stress. Modifying the network structure of silicate glasses, such as pure fused silica with elements such as B, Al, F, etc., can offer higher shock resistance, tunability, and impede amorphous to crystallization transitions, which commonly occur in pure fused silica. In this talk, we investigated the dynamical response of network-modified silicate glasses under laser-driven shock compression up to ~130 GPa, using in-situ x-ray diffraction at Linac Coherent Light Source. Both B-doped and Al-doped fused silica glass transformed to the stishovite phase at ~50 GPa. However, Al-doped glass had higher crystallinity under shock compression compared to B-doped glass. Furthermore, the Al-doped glass undergoes crystallization 1-2 ns earlier compared to the B-doped, for the same pressure range. For both systems, we also observed a transition to the d-niccolite phase at higher pressures >65 GPa. We also mapped out the phase transformation as a function of pressure to show clear points of distinction from pure fused silica. Our studies provide a nanoscale understanding of underlying nucleation and growth mechanisms in network-modified silicate glasses and provide insights into transient state properties under laser-driven shock dynamics.