Spin correlations in nonperturbative electron-positron pair creation by petawatt laser pulses colliding with a TeV proton beam

强激光场与轫致辐射γ射线或相对论离子碰撞产生非微扰正负电子对的对比研究

Comparative study of nonperturbative electron-positron pair production by intense laser fields colliding with either bremsstrahlung $γ$-rays or relativistic ions

该研究对比了强激光场与轫致辐射γ射线、相对论离子碰撞产生非微扰正负电子对的过程，发现合适参数下二者总速率物理性质相近，可利用前者实验模拟后者。

Multi-channel Interference in Nonperturbative Multiphoton Pair Production by Gamma Rays Colliding

The electron-positron pair production in the collision of two intense gamma lasers is studied beyond the dipole approximation. The complete electron/positron momentum spectrum obtained by three-dimensional computation shows directly the multi-photon pair production channels and provides a sensitive test on the widely-used concept of the effective mass. Nonperturbative features are identified in the dependence of the total yield on the field intensity. In particular, various breaks in the momentum rings are observed and proved to be a manifestation of particle's energy gaps in the standing ligh…

Nonperturbative Bethe-Heitler pair creation in combined high- and low-frequency laser fields

The nonperturbative regime of electron-positron pair creation by a relativistic proton beam colliding with a highly intense bichromatic laser field is studied. The laser wave is composed of a strong low-frequency and a weak high-frequency mode, with mutually orthogonal polarization vectors. We show that the presence of the high-frequency field component can strongly enhance the pair-creation rate. Besides, a characteristic influence of the high-frequency mode on the angular and energy distributions of the created particles is demonstrated, both in the nuclear rest frame and the laboratory fram…

On Seminal HEDP Research Opportunities Enabled by Colocating Multi-Petawatt Laser with High-Density Electron Beams

The scientific community is currently witnessing an expensive and worldwide race to achieve the highest possible light intensity. Within the next decade this effort is expected to reach nearly $10^{24}\,\mathrm{W}/\mathrm{cm^2}$ in the lab frame by focusing of 100 PW, near-infrared lasers. A major driving force behind this effort is the possibility to study strong-field vacuum breakdown and an accompanying electron-positron pair plasma via a quantum electrodynamic (QED) cascade [Edwin Cartlidge, "The light fantastic", Science 359, 382 (2018)]. Whereas Europe is focusing on all-optical 10 PW-cl…

以更高音调寻找轴子：高强度激光束对撞产生的三次谐波

Searching for Axions on a Higher Note: Third-Harmonic Generation from Colliding High-Intensity Laser Beams

该研究提出利用两束约$10^{24}\\,\mathrm{W/cm^2}$的非共线偏振高强度激光对撞产生的三次谐波，实现类轴子粒子的生成与探测，可共振增强转换率，有望探测未被探索的轴子参数空间区域。

Momentum distribution of particles created in space-time-dependent colliding laser pulses

We study the pair-production process in the presence of two counterpropagating linearly polarized short laser pulses. By means of a nonperturbative technique, we take into account the full coordinate dependence of the external field going beyond the dipole and standing-wave approximations. In particular, we analyze the momentum distribution of particles created. It is demonstrated that the spatial variations of the laser pulses may play a crucial role. The more accurate treatment reveals a number of prominent features: the pair-production probabilities become considerably smaller, the quantita…