Quasi-monoenergetic electron beams from a few-terawatt laser driven plasma acceleration using a nitrogen gas jet

摘要

An experimental investigation on the laser plasma acceleration of electrons has been carried out using 3 TW, 45 fs duration titanium sapphire laser pulse interaction with a nitrogen gas jet at an intensity of 2 x 10(18) Wcm(-2). We have observed the stable generation of a well collimated electron beam with divergence and pointing variation similar to 10 mrad from nitrogen gas jet plasma at an optimum plasma density around 3 x 10(19) cm(-3). The energy spectrum of the electron beam was quasi-monoenergetic with an average peak energy and a charge around 25 MeV and 30 pC respectively. The results will be useful for better understanding and control of ionization injection and the laser wakefield acceleration ( LWFA) of electrons in high-Z gases and also towards the development of practical LWFA for various applications including injectors for high energy accelerators.