Two-temperature hydrodynamic expansion and coupling of strong elastic shock with supersonic melting front produced by ultrashort laser pulse

18th APS-SCCM; 24th AIRAPT

Inogamov, Nail A.^1 ; Zhakhovsky, Vasily V^2,3 ; Khokhlov, Viktor A^1 ; Demaske, Brian J^3 ; Khishchenko, Konstantin V^2 ; Oleynik, Ivan I^3

Landau Institute for Theoretical Physics, Russian Academy of Sciences, Russia^1

Joint Institute for High Temperatures of Russian Academy of Sciences, Russian Federation, Russia^2

Department of Physics, University of South Florida, Tampa

FL, United States^3

关键词: Effective tensile strength;    Electron pressures;    Expanding materials;    Homogeneous melting;    Hydrodynamic expansion;    Material expansion;    Supersonic propagation;    Ultrafast process;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/19/192023/pdf
DOI  :  10.1088/1742-6596/500/19/192023

来源: IOP

【 摘 要 】

Ultrafast processes, including nonmonotonic expansion of material into vacuum, supersonic melting and generation of super-elastic shock wave, in a surface layer of metal irradiated by an ultrashort laser pulse are discussed. In addition to the well-established two-temperature (2T) evolution of heated layer a new effect of electron pressure gradient on early stage of material expansion is studied. It is shown that the expanding material experiences an unexpected jump in flow velocity in a place where stress exceeds the effective tensile strength provided by used EoS of material. Another 2T effect is that supersonic propagation of homogeneous melting front results in distortion of spatial profile of ion temperature, which later imprints on ion pressure profile transforming in a super-elastic shock wave with time.