The electron spin in strong field tunnelionization

强场隧道电离中的电子自旋

• 批准号: 272257846
• 负责人: Professor Dr. Reinhard Dörner
• 金额: --
• 依托单位: Institut für Kernphysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/272257846?language=en
• 关键词: electron; spin; strong; field; tunnelionization

Tunneling through a rotating barrier is spin selective. This is, in short, the surprising prediction of a series of recent theoretical papers by Barth and Smirnova. The present project aims at performing the first experimental test of that prediction. Nowadays, Titan Sapphire-based femtosecond-lasers allow to routinely reach intensities in the range of 1014 W/cm2 and higher at a wavelength of 800 nm (which is equivalent to an energy of 1.5 eV per photon). Atoms or molecules exposed to such a strong laser pulse are efficiently ionized by field induced tunneling. For circularly polarized light the tunnel barrier, that needs to be overcome by the ionized electron, is rotating. The above mentioned novel theoretical work predicts a high degree of spin polarization of electrons emitted by strong field tunnel ionization from rare gas atoms in case circularly polarized laser pulses are employed. This far reaching prediction still needs experimental confirmation. Therefore the goal of the present experimental proposal is to perform a series of experiments to test this theory in detail. We propose to shoot a strong and short circularly polarized laser pulse on rare gas atoms and measure the degree of spin polarization as function of the electron energy of the emitted electron for different atomic species, different intensities and different wavelengths. In addition to verifying the predicted effect its assumed underlying physical explanation can be tested by varying the parameters wavelength, field strength and binding energy of the emitted electron. Preparatory work by the group of the applicant has already been performed and yielded very promising results. If successful the project will be extended to molecules and also laser aligned molecules in a second funding period.

穿过旋转势垒的隧穿是自旋选择性的。简而言之，这是巴思和斯米尔诺娃最近发表的一系列理论论文中令人惊讶的预测。本项目旨在对这一预测进行第一次实验测试。如今，基于Titan Sapphire的飞秒激光器允许在800 nm波长处常规地达到1014 W/cm 2和更高范围内的强度（这相当于每光子1.5 eV的能量）。暴露于如此强的激光脉冲的原子或分子通过场致隧穿而有效地电离。对于圆偏振光，需要被电离电子克服的隧道势垒是旋转的。上述新的理论工作预言了在采用圆偏振激光脉冲的情况下，由稀有气体原子的强场隧道电离发射的电子的高度自旋极化。这个意义深远的预言仍需实验证实。因此，本实验方案的目标是进行一系列实验来详细测试该理论。我们提出了一个强大的和短的圆偏振激光脉冲拍摄稀有气体原子和测量自旋极化程度的函数的电子能量的发射电子的不同原子种类，不同的强度和不同的波长。除了验证所预测的效应之外，还可以通过改变参数波长、场强和发射电子的结合能来测试其假定的基本物理解释。如果成功，该项目将在第二个资助期内扩展到分子和激光对准分子。

项目成果

Measurement of the spin polarization of electrons in a strong laser field

强激光场中电子自旋极化的测量

• DOI: 10.1088/1742-6596/635/9/092069
• 发表时间: 2015
• 期刊: Journal of Physics: Conference Series
• 作者: Alexander Hartung;Alina Laucke;Maksim Kunitski;Reinhard Dörner
• 通讯作者: Reinhard Dörner

Spin and Angular Momentum in Strong-Field Ionization.

• DOI: 10.1103/physrevlett.120.043202
• 发表时间: 2017-11
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: D. Trabert;A. Hartung;S. Eckart;F. Trinter;A. Kalinin;M. Schöffler;L. Schmidt;T. Jahnke;M. Kunitski;R. Dörner

Electron spin polarization in strong-field ionization and the effect of spin in attoclock measurements

强场电离中的电子自旋极化以及自旋在时钟测量中的影响

• DOI: 10.1109/cleoe-eqec.2017.8086812
• 发表时间: 2017
• 期刊: 2017 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)
• 作者: Morales;Kaushal;Hartung;Kunitski;Henrichs;Laucke;Richter;Jahnke;Kalinin;Schoffler;Schmidt;Dorner;Ivanov;Smirnova
• 通讯作者: Smirnova