论文简介 |
The production of a highly polarized positron beam via nonlinear Breit-Wheeler processes during the
interaction of an ultraintense circularly polarized laser pulse with a longitudinally spin-polarized ultrarelativistic electron beam is investigated theoretically. A new Monte Carlo method employing fully
spin-resolved quantum probabilities is developed under the local constant field approximation to include
three-dimensional polarization effects in strong laser fields. The produced positrons are longitudinally
polarized through polarization transferred from the polarized electrons by the medium of high-energy
photons. The polarization transfer efficiency can approach 100% for the energetic positrons moving at smaller
deflection angles. This method simplifies the postselection procedure to generate high-quality positron beams
in further applications. In a feasible scenario, a highly polarized (40%–65%), intense (105–106/bunch),
collimated (5–70 mrad) positron beam can be obtained in a femtosecond timescale. The longitudinally
polarized positron sources are desirable for applications in high-energy physics and material science.
Yan-Fei Li ,1,* Yue-Yue Chen,2,† Wei-Min Wang ,3,4,5 and Hua-Si Hu1,‡ 1
Department of Nuclear Science and Technology, School of Energy and Power Engineering, Xi’an Jiaotong University,
Xi’an 710049, China 2
Department of Physics, Shanghai Normal University, Shanghai 200234, China 3
Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices,
Renmin University of China, Beijing 100872, China 4
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, CAS, Beijing 100190, China
5
Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
(Received 2 March 2020; revised 17 May 2020; accepted 25 June 2020; published 21 July 2020)
*liyanfei@xjtu.edu.cn
†yueyuechen@shnu.edu.cn
‡huasi_hu@mail.xjtu.edu.cn
The authors thank Y.-T. Li and K. Z. Hatsagortsyan for
helpful discussions. This work is supported by the National
Natural Science Foundation of China (Grants
No. 11804269, No. U1830128, and No. 11775302), the
National Key R&D Program of China (Grant
No. 2018YFA0404801), the Strategic Priority Research
Program of Chinese Academy of Sciences (Grant
No. XDA25050300), the Program for Professor of
Special Appointment (Eastern Scholar) at Shanghai
Institutions of Higher Learning, Shanghai Rising-Star
Program, the Fundamental Research Funds for the
Central Universities, and the Research Funds of Renmin
University of China (20XNLG01).
DOI: 10.1103/PhysRevLett.125.044802 |