title: Dense GeV electron-positron pairs generated by lasers in near-critical-density plasmas.
abstract: Pair production can be triggered by high-intensity lasers via the Breit-Wheeler process. However, the straightforward laser-laser colliding for copious numbers of pair creation requires light intensities several orders of magnitude higher than possible with the ongoing laser facilities. Despite the numerous proposed approaches, creating high-energy-density pair plasmas in laboratories is still challenging. Here we present an all-optical scheme for overdense pair production by two counter-propagating lasers irradiating near-critical-density plasmas at only ∼1022W cm-2. In this scheme, bright γ-rays are generated by radiation-trapped electrons oscillating in the laser fields. The dense γ-photons then collide with the focused counter-propagating lasers to initiate the multi-photon Breit-Wheeler process. Particle-in-cell simulations indicate that one may generate a high-yield (1.05 × 1011) overdense (4 × 1022cm-3) GeV positron beam using 10 PW scale lasers. Such a bright pair source has many practical applications and could be basis for future compact high-luminosity electron-positron colliders.
authors.affiliation: College of Science, National University of Defense Technology, Changsha 410073, China.
authors.forename: Xing-Long
authors.initials: XL
authors.lastname: Zhu
authors.affiliation: College of Science, National University of Defense Technology, Changsha 410073, China.|Collaborative Innovation Center of IFSA (CICIFSA), Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Tong-Pu
authors.initials: TP
authors.lastname: Yu
authors.affiliation: Collaborative Innovation Center of IFSA (CICIFSA), Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.|SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK.
authors.forename: Zheng-Ming
authors.initials: ZM
authors.lastname: Sheng
authors.affiliation: College of Science, National University of Defense Technology, Changsha 410073, China.
authors.forename: Yan
authors.identifier: 0000-0002-4969-0714
authors.initials: Y
authors.lastname: Yin
authors.affiliation: School of Electronic Science and Engineering, Nanjing University, Nanjing 210023, China.|National Institute for Physics and Nuclear Engineering, ELI-NP, Str Reactorului, nr. 30, P.O.Box MG-6, Bucharest-Magurele 077125, Romania.|Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, UK.
authors.forename: Ion Cristian Edmond
authors.initials: IC
authors.lastname: Turcu
authors.affiliation: Institut für Theoretische Physik I, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Pukhov