Laser pulse focusing and energetic electron generation by magnetised plasma lens

An efficient novel mechanism of laser pulse focusing with the help of a shaped underdense plasma target immersed in an inhomogeneous magnetic field has been demonstrated. These studies have been carried out with the help of two-dimensional particle-in-cell simulation employing the OSIRIS 4.0 platform. It is shown that the divergent magnetic field profile compresses the electromagnetic wave pulse in the transverse direction. A comparative investigation with plane and lens-shaped plasma geometries has also been conducted to find an optimal configuration for focusing the laser at the desirable location. Furthermore, it is also demonstrated that, when the electron cyclotron resonance layer is placed at a suitable location where the laser is focused, a highly energetic electron beam is generated.