Quasimonoenergetic proton bunch generation by dual-peaked electrostatic-field acceleration in foils irradiated by an intense linearly polarized laser

• Published in: Physical review letters Vol. 105; no. 6; p. 065003
• Main Authors: Zhuo, H B, Chen, Z L, Yu, W, Sheng, Z M, Yu, M Y, Jin, Z, Kodama, R
• Format: Journal Article
• Language: English
• Published: United States 06-08-2010
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; BEAM BUNCHING; BEAM DYNAMICS; BEAM PRODUCTION; BEAM-PLASMA SYSTEMS; BEAMS; COMPUTERIZED SIMULATION; CONVERSION; DYNAMICS; ENERGY CONVERSION; ENERGY RANGE; FOILS; GEV RANGE; LASER-PRODUCED PLASMA; LASERS; MECHANICS; MEV RANGE; NUCLEON BEAMS; PARTICLE ACCELERATORS; PARTICLE BEAMS; PLASMA; PLASMA SIMULATION; PONDEROMOTIVE FORCE; PROTON BEAMS; RADIATION PRESSURE; SIMULATION; TWO-DIMENSIONAL CALCULATIONS
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/physrevlett.105.065003

It is found that stable proton acceleration from a thin foil irradiated by a linearly polarized ultraintense laser can be realized for appropriate foil thickness and laser intensity. A dual-peaked electrostatic field, originating from the oscillating and nonoscillating components of the laser ponderomotive force, is formed around the foil surfaces. This field combines radiation-pressure acceleration and target normal sheath acceleration to produce a single quasimonoenergetic ion bunch. A criterion for this mechanism to be operative is obtained and verified by two-dimensional particle-in-cell simulation. At a laser intensity of ∼5.5×10(22)  W/cm(2), quasimonoenergetic GeV proton bunches are obtained with ∼100  MeV energy spread, less than 4° spatial divergence, and ∼50% energy conversion efficiency from the laser.