Picosecond-scale heterogeneous melting of metals at extreme non-equilibrium states.

ABSTRACT: Extreme electron-ion non-equilibrium states, generated by ultrafast laser excitation, lead to melting processes that are fundamentally different from those under conventional thermal equilibrium and remain not fully understood. Through neural network-enhanced multiscale simulations of tungsten and gold nanofilms, we identify electronic pressure relaxation as critical to heterogeneous phase transformations. This nonthermal expansion generates a density decrease that enable surface-initiated melting far below equilibrium melting temperatures, creating electronic pressure-driven solid-liquid interface propagation at a high speed of 2500 ms^-1-tenfold faster than that of thermal heterogeneous melting mechanisms. Simulated time-resolved X-ray diffraction signatures distinguish this no

SUBMITTER: Zeng Q 

PROVIDER: S-EPMC12647707 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature