Prof.  Pawan  Kumar
Raj Kumar Goel Institute of Technology, Ghaziabad,  India

Title: High Power Terahertz Radiation Generation from Laser Plasma Interaction

Abstract:

Plasma is an ionized state of matter. Its response to electromagnetic fields is inherently nonlinear. It produces coherent terahertz radiation when a pair of picosecond lasers with frequency difference equal to plasma frequency propagates through it in the presence of a density ripple. The density ripple compensates for the momentum mismatch between the pump lasers and the generated terahertz wave. It also provides mandatory transverse component to the induced current density, to produce electromagnetic terahertz radiation. The efficiency of THz generation is significantly enhanced with the application of a static magnetic field. We also found resonant enhancement in THz efficiency via electromagnetic wave-Langmuir wave coupling when lasers are obliquely impinged on a sharp boundary plasma and the plasma frequency is slightly lower than the frequency difference of lasers. We discuss the fascinating physics of these processes.

Biography:

Research Interests
Fundamentals of Plasma Physics, Radio Frequency Heating of Plasmas, Laser Plasma Interaction, FELs, Coherent Radiations Generation. Light Matter Interaction at Nanoscale, Nanostructured Plasmas, THz Plasmonics, Graphene Based Radiation Sources