题　目：Spin effects in the Kapitza-Dirac effect
报告人：Dr. Sven Ahrens（Postdoc in Beijing Computational Science Research Center）

时　间：5月5日（周一），上午10:00-11:00
地　点：物理馆512会议室

报告摘要：

The Kapitza-Dirac effect [1], which is the diffraction of electrons at a standing wave of light, has been observed experimentally in the last decade [2]. The availability of novel high intensity X-ray laser sources calls for a relativistic description of this electron scattering process.

I discuss the quantum dynamics of the electron diffraction by solvingthe Dirac equation in momentum space [3]. Spin-effects can be found2-photon Kapitza-Dirac effect scattering as well a generalized 3-photonKapitza-Dirac effect [4]. In my talk I will focus on the occurence of the 2- and 3-photon Kapitza-Dirac effect and demonstrate, that it features a tunable electron spin-flip probability.

[1] P. L. Kapitza, P. A. M. Dirac, Proc. Cambridge Philos. Soc. 29, 297–300 (1933)

[2] D. L. Freimund, K. Aflatooni, H. Batelaan, Nature 413, 142–143 (2001)

[3] S. Ahrens, H. Bauke, C. H. Keitel, C. Müller, Phys. Rev. Lett. 109, 043601 (2012)

[4] S. Ahrens, H. Bauke, C. H. Keitel, C. Müller, Phys. Rev. A 88, 012115 (2013) 

个人简介：

Dr. Sven Ahrens was born on Feb 23, 1983 in Erfurt of German. His research interests are photonic crystal and metamaterials as well as relativistic quantum dynamics with the Dirac equation.

*2004-2006       BSc of Science: Technische Universität Darmstadt, German

*2006-2008       Msc of Science: Technische Universität Darmstadt, German

*2008-2012       Ph.D in Physics: Ruprecht-Karls-Universität Heidelberg, German

*2012.11-2013.12  Postdoc: Max-Planck-Institut für Kernphysik

*2014.1-2014.2    Inst. Asst. Professor: Illinois State University, USA

*2014.3-present    Postdoc: Beijing Computational Science Research Center