Wang Run, Zhang Qingbin, Ran Cheng, Cao Wei, Lu Peixiang
Opt Lett. 2020 Mar 15;45(6):1383-1386. doi: 10.1364/OL.388516.
In an intense circularly polarized laser field, the excitation of the atoms shows a strong dependence on the orbital helicity. The resonant excitation starting from the ground state with $ m = - 1 $m=-1 occurs much more easily in the left-handed circularly polarized (LCP with $ m = + 1 $m=+1) pulse than in the right-handed circularly polarized (RCP with $ m = - 1 $m=-1) pulse. In this Letter, we numerically demonstrate that the orbital-helicity-dependent two-photon-resonant excitation leads to the photoelectron vortex pattern in the polarization plane being sensitive to the sequence of the two counter-rotating circularly polarized pulses in xenon, which enables the detection of the ring currents associated with different quantum states. These results also provide an effective way for controlling the rotational symmetry of the electron vortex.
在强圆偏振激光场中，原子的激发表现出对轨道螺旋度的强烈依赖性。从基态(m = -1)开始的共振激发，在左旋圆偏振（(m = +1)的LCP）脉冲中比在右旋圆偏振（(m = -1)的RCP）脉冲中更容易发生。在本信函中，我们通过数值证明，依赖于轨道螺旋度的双光子共振激发导致氙中偏振平面内的光电子涡旋图案对两个反向旋转圆偏振脉冲的顺序敏感，这使得能够检测与不同量子态相关的环形电流。这些结果还为控制电子涡旋的旋转对称性提供了一种有效方法。
