One-dimensional PIC simulation of ultrashort laser pulse amplification in a plasma by a counterpropagating pump

Summary form only given. It is necessary to generate an ultrahigh intensity subpicosecond laser pulse for application to the laser wakefield accelerator (LWFA) or inertial confinement fusion (ICF). For the achievement of above petawatt (10/sup 15/ W) laser power, both conventional amplifiers and the chirp pulse amplification (CPA) technique are not adequate because they have limitation of laser intensity to GW/cm/sup 2/ and TW/cm/sup 2/, respectively. For more powerful amplification, it has been shown that three wave interaction between the counterpropagating electromagnetic waves and a plasma wave can generate superradiant amplification of a short laser pulse. In this study, we simulate the amplification of a short laser pulse by a counterpropagating pump in a plasma. We use the one dimensional version of XOOPIC, an object-oriented particle-in-cell code. Two plane waves are launched from opposite sides of the plasma. For appropriately chosen parameters the energy of the pump probe can be transferred to the ultra-short pulse. Energy gain, compression of the short pulse, and pump depletion are studied with the simulation for a wide variety of system parameters such as intensity of pump wave, frequency, plasma density, and pulse shape. The simulation results are compared with theoretical predictions.