Probing ultrafast dynamics in a solid-density plasma created by an intense femtosecond laser

8th International Conference on Inertial Fusion Sciences and Applications

Adak, Amitava^1 ; Blackman, Dave^2 ; Chatterjee, Gourab^1 ; Singh, Prashant Kumar^1 ; Lad, Amit D.^1 ; Brijesh, P.^1 ; Robinson, A.P.L.^3 ; Pasley, John^2,3 ; Ravindra Kumar, G.^1

Tata Institute of Fundamental Research, Dr. Homi Bhabha Road, Colaba, Mumbai

400005, India^1

York Plasma Institute, University of York, Heslington

YO10 5DQ, United Kingdom^2

Central Laser Facility, Rutherford Appleton Laboratory, Chilton-Didcot

OX10 0QX, United Kingdom^3

关键词: Critical density;    Femtosecond pump lasers;    Femtoseconds;    Laser driven shocks;    Probe laser pulse;    Solid density plasmas;    Time-resolved;    Ultra-fast dynamics;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/688/1/012001/pdf
DOI  :  10.1088/1742-6596/688/1/012001

来源: IOP

【 摘 要 】

We report a study on the dynamics of a near-solid density plasma using an ultraviolet (266 nm) femtosecond probe laser pulse, which can penetrate to densities of ∼ 1022cm-3, nearly an order of magnitude higher than the critical density of the 800 nm, femtosecond pump laser. Time-resolved probe-reflectivity from the plasma shows a rapid decay (picosecond- timescale) while the time-resolved reflected probe spectra show red shifts at early temporal delays and blue shifts at longer delays. This spectral behaviour of the reflected probe can be explained by a laser-driven shock moving inward and a subsequent hydrodynamic free expansion in the outward direction.