Abstract
The authors propose a scheme utilizing an underdense plasma of spiral thickness in generating relativistic vortex laser light with axial orbital angular momentum. The laser ponderomotive and the plasma charge-separation forces exert a torque on the plasma ions, resulting in creation of oppositely directed forces in the plasma ions and the laser light.
Highlights
Three-dimensional particle-in-cell simulations show that relativistic Gaussian laser light can be transformed into relativistic vortex laser light with axial orbital angular momentum (OAM) as it propagates through a homogeneous spiral-profiled low-density plasma slab
Because of the azimuthally varying slab thickness, the laser ponderomotive and the charge-separation forces exert a torque on the plasma when it passes through it, resulting in the creation of oppositely directed OAM in the plasma ions and the laser light, with the electrons remaining nearly OAM free
Depending on the light polarization and azimuthal phase profile, the total angular momentum (AM) of light consists of spin angular momentum (SAM) and orbital angular momentum (OAM) [1]
Summary
Depending on the light polarization and azimuthal phase profile, the total angular momentum (AM) of light consists of spin angular momentum (SAM) and orbital angular momentum (OAM) [1]. An ideal Laguerre-Gaussian pulse with helical phase dependence exp(−ilφ − ikx) has a well-defined average OAM value l hper photon, where k is the wave vector in the axial or propagation direction x, φ is the azimuthal angle, and l is a mode index, or the topological charge. We propose a scheme for obtaining relativistic vortex light in the same direction of the incident laser. The latter, of high intensity and arbitrary polarization, irradiates a low-density plasma slab with azimuthally varying thickness, which modulates and warps the initially plane light-wave phases into a continuous spiral structure.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
