Energy Enhancement of the Self-Modulated Laser Wakefield Acceleration using the Plasma Density Gradient

Many laser wakefield acceleration experiments have been operated in the high power, long pulse, self-modulated regime. But there are strong instabilities and electron dephasing problem due to the velocity difference between the electron beam and the wake wave. Our simulation study shows that the upward density gradient scheme can be used to avoid the dephasing problem. Moreover, we present a brief plan of ongoing experimental research using the laser system at Korea Electrotechnology Research Institute (KERI).