2009 年 52 巻 8 号 p. 430-436
In laser-driven plasma acceleration, which is charged particle acceleration via the interaction of an intense laser pulse with a plasma, the accelerating electric field is a thousand times higher than that of conventional radio-frequency accelerators. Such high accelerating field enables a compact accelerator. Recently, the generation of quasi-monoenergetic electron beams has been demonstrated and the way toward a practical, compact electron accelerator is opened. Furthermore, the electron pulse duration is extremely short, of the order of femtosecond in laser-driven plasma acceleration. This set of unique characteristics opens the way toward a novel, compact, all-optical, ultrashort X-ray source based on such as laser Compton scattering scheme. The present status of the quasi-monoenergetic electron acceleration and prospect for all-optical ultrashort X-ray sources are reviewed.