Li Yan-Fei, Chen Yue-Yue, Hatsagortsyan Karen Z, Keitel Christoph H
Department of Nuclear Science and Technology, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Department of Physics, Shanghai Normal University, Shanghai 200234, China.
Phys Rev Lett. 2022 Apr 29;128(17):174801. doi: 10.1103/PhysRevLett.128.174801.
Electron beam longitudinal polarization during the interaction with counterpropagating circularly polarized ultraintense laser pulses is investigated, while accounting for the anomalous magnetic moment of the electron. Although it is known that the helicity transfer from the laser photons to the electron beam is suppressed in linear and nonlinear Compton scattering processes, we show that the helicity transfer nevertheless can happen via an intermediate step of the electron radiative transverse polarization, phase matched with the driving field, followed up by spin rotation into the longitudinal direction as induced by the anomalous magnetic moment of the electron. With spin-resolved QED Monte Carlo simulations, we demonstrate the consequent helicity transfer from laser photons to the electron beam with a degree up to 10%, along with an electron radial polarization up to 65% after multiple photon emissions in a femtosecond timescale. This effect is detectable with currently achievable laser facilities, evidencing the role of the leading QED vertex correction to the electron anomalous magnetic moment in the polarization dynamics in ultrastrong laser fields.
研究了电子束在与反向传播的圆偏振超强激光脉冲相互作用期间的纵向极化，同时考虑了电子的反常磁矩。尽管已知在线性和非线性康普顿散射过程中，从激光光子到电子束的螺旋度转移受到抑制，但我们表明，螺旋度转移仍可通过电子辐射横向极化的中间步骤发生，该步骤与驱动场相位匹配，随后由电子的反常磁矩诱导自旋旋转到纵向方向。通过自旋分辨的量子电动力学蒙特卡罗模拟，我们展示了随后从激光光子到电子束的螺旋度转移，转移程度高达10%，并且在飞秒时间尺度上多次光子发射后，电子径向极化高达65%。这种效应在当前可实现的激光设施中是可检测的，证明了电子反常磁矩的主导量子电动力学顶点修正在超强激光场极化动力学中的作用。
