All-optical quasi-monoenergetic GeV positron bunch generation by twisted laser fields

Zhao, Jie and Hu, Yan-Ting and Lu, Yu and Zhang, Hao and Hu, Li-Xiang and Zhu, Xing-Long and Sheng, Zheng-Ming and Turcu, Ion Cristian Edmond and Pukhov, Alexander and Shao, Fu-Qiu and Yu, Tong-Pu (2022) All-optical quasi-monoenergetic GeV positron bunch generation by twisted laser fields. Communications Physics, 5 (1). 15. ISSN 2399-3650 (https://doi.org/10.1038/s42005-021-00797-9)

[thumbnail of Zhao-etal-CP-2022-All-optical-quasi-monoenergetic-GeV-positron-bunch-generation-by-twisted-laser-fields]
Preview
Text. Filename: Zhao_etal_CP_2022_All_optical_quasi_monoenergetic_GeV_positron_bunch_generation_by_twisted_laser_fields.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (1MB)| Preview

Abstract

Abstract: Generation of energetic electron-positron pairs using multi-petawatt (PW) lasers has recently attracted increasing interest. However, some previous laser-driven positron beams have severe limitations in terms of energy spread, beam duration, density, and collimation. Here we propose a scheme for the generation of dense ultra-short quasi-monoenergetic positron bunches by colliding a twisted laser pulse with a Gaussian laser pulse. In this scheme, abundant γ-photons are first generated via nonlinear Compton scattering and positrons are subsequently generated during the head-on collision of γ-photons with the Gaussian laser pulse. Due to the unique structure of the twisted laser pulse, the positrons are confined by the radial electric fields and experience phase-locked-acceleration by the longitudinal electric field. Three-dimensional simulations demonstrate the generation of dense sub-femtosecond quasi-monoenergetic GeV positron bunches with tens of picocoulomb (pC) charge and extremely high brilliance above 1014 s−1 mm−2 mrad−2 eV−1, making them promising for applications in laboratory physics and high energy physics.