Chirality causes symmetry breaks in a large variety of natural phenomena ranging from particle physics to biochemistry. We investigate one of the simplest conceivable chiral systems, a laser-excited, oriented, effective one-electron Li target. Prepared in a polarized $p$ state with $|m|=1$ in an optical trap, the atoms are exposed to co- and counterrotating circularly polarized femtosecond laser pulses. For a field frequency near the excitation energy of the oriented initial state, a strong circular dichroism is observed and the photoelectron energies are significantly affected by the helicity-dependent Autler-Townes splitting. Besides its fundamental relevance, this system is suited to create spin-polarized electron pulses with a reversible switch on a femtosecond timescale at an energy resolution of a few meV.

中文翻译：

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使用圆二色性控制多光子电离中的能量转移

手性导致从粒子物理学到生物化学的各种自然现象的对称性破裂。我们研究了最简单的一种手性体系，一种激光激发的，定向的，有效的单电子锂靶。在偏光下准备$p$ 与 $|米|=\mathrm{1个}$在光阱中，原子暴露于同向和反向旋转的圆偏振飞秒激光脉冲。对于接近于取向的初始状态的激发能的场频率，观察到强的圆二色性，并且光电子能量受到依赖于螺旋度的奥特勒-唐兹分裂的显着影响。除了其基本意义外，该系统还适合于在飞秒时标上以几毫伏的能量分辨率产生带有可逆开关的自旋极化电子脉冲。