Polarization and phase control of electron injection and acceleration in the plasma by a self-steepening laser pulse

• Published in: New journal of physics Vol. 25; no. 3; pp. 33009 - 33029
• Main Authors: Kim, Jihoon, Wang, Tianhong, Khudik, Vladimir, Shvets, Gennady
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.03.2023
• Subjects: Angular distribution; carrier-envelope-phase; Electron beams; Energy distribution; Energy spectra; laser wakefield accelerators; Lasers; Phase control; Physics; Plasma; Plasma bubbles; plasma physics; Polarization; Pulse propagation; x-ray generation
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/acbed5

Abstract We describe an interplay between two injection mechanism of background electrons into an evolving plasma bubble behind an intense laser pulse: one due to the overall bubble expansion, and another due to its periodic undulation. The two mechanisms occur simultaneously when an intense laser pulse propagating inside a plasma forms a shock-like steepened front. Periodic undulations of the plasma bubble along the laser propagation path can either inhibit or conspire with electron injection due to bubble expansion. We show that carrier-envelope-phase (CEP) controlled plasma bubble undulation induced by the self-steepening laser pulse produces a unique electron injector—expanding phase-controlled undulating bubble (EPUB). The longitudinal structure of the electron bunch injected by the EPUB can be controlled by laser polarization and power, resulting in high-charge (multiple nano-Coulombs) high-current (tens of kilo-amperes) electron beams with ultra-short (femtosecond-scale) temporal structure. Generation of high-energy betatron radiation with polarization- and CEP-controlled energy spectrum and angular distribution is analyzed as a promising application of EPUB-produced beams.