arXiv subjects

Roopendra Rajawat

Publications and source records attributed to Roopendra Rajawat.

2 recordsLinked to original sources

arXiv2025

Simultaneous amplification and shaping of excimer lasers using Stimulated Brillouin Scattering in the strongly damped limit

Attaining practical Inertial Fusion Energy (IFE) depends on how efficiently one can couple the driver energy to the nuclear fusion fuel for compression and ignition. While the excimer lasers provide an efficient alternative compared to existing laser technology, it is unclear how the lasers can be harnessed to form a pulse with desired pulse shape and intensity. Stimulated Brillouin Scattering (SBS) provides a path to compressing long, energetic pulses to short intense ones. We consider the equations governing SBS in the Strongly Damped Limit (SDL) and find that it is possible to almost completely specify the final pulse shape by providing an appropriate initial seed pulse. We provide analytic expressions for reverse-engineering the initial seed shape and delineate physical limits concerning the prepulse level.

physics.optics↗

arXiv2024

Acceleration and focusing of multispecies ion beam using a converging laser-driven shock

We demonstrate an ion acceleration scheme capable of simultaneously focusing and accelerating a multispecies ion beam with monoenergetic spectra to a few micron radius. The focal length and ion mean energy can be independently controlled: the former by using a different front-surface shape and the latter by tuning the laser-plasma parameters. We interpret the results using simple models and validate the results using first-principles simulations. The scheme is applicable to different laser transverse profiles and multi-ion species target, and limiting factors for the ion focusing are delineated. The generated ion beam exhibits high charge, low emittance, and high energy flux and is of interest to various applications including Inertial Confinement Fusion (ICF), high flux neutron generation, and biomedical applications.

physics.plasm-ph↗