Generation of intense magnetic fields using orbital angular momentum modes of light in plasmas

Summary form only given. Circularly polarized light has been successfully used to generate high strength axial magnetic fields in plasmas using high intensity laser pulses. These strong magnetic fields have been able to reach magnitudes approaching 1000 Tesla [1]. High strength magnetic fields have potential uses for guiding electron beams onto targets, such as for fast ignition of laser compressed fusion targets. Recent interest in orbital angular momentum (OAM) modes has shown that even linearly polarized light can potentially give rise to axial magnetic fields [2,3]. Laguerre-Gaussian (LG) modes carry both spin and OAM, generated by the rotating wave vector as opposed to that of a plane wave which contains only a spin component. In this work, the mathematics, geometry and simulation of the modes are discussed together with approaches to generating these OAM modes without the use of a spatial light modulator (SLM). Currently an experiment is being prepared to create such OAM modes using phase plates, while measurements of the magnetic field strengths produced will be measured using Zeeman splitting of bound-bound transitions of ion species in the plasma. Imaging the fields using inverse Faraday rotation measurements will also be investigated. The generation of such fields and the initial proposed measurements will be discussed.