【讲座题目】X-ray pump-probe spectroscopy of electron-nuclear dynamics
【主 讲 人】Victor Kimberg 研究员
【讲座时间】2024年4月28日 星期日上午10:30-11:30
【讲座地点】主楼D座603
【主讲人简介】瑞典皇家工学院化学系研究员，博士生导师。主要从事原子、分子、光物理及光谱学方面的研究，重点关注光与物质相互作用超快动力学过程，包括VUV及X射线场在原子分子介质中的辐射、传播过程及相应的光谱学研究。已在Review of Modern Physics、Nature Physics、PRL、PRX等发表学术论文多篇，主持包括瑞典研究委员会、瑞典科研与教育国际合作基金会、俄罗斯科学基金会、俄罗斯基础研究基金会等科研项目多项。
【讲座内容简介】X-ray Free Electron laser (XFEL) and high harmonic generation (HHG) sources have opened a new era in science, providing ultrashort, coherent and tunable pulses that enables new types of pump-probe techniques to perform cutting edge experiments in atomic and molecular physics, condensed matter physics, biology, and chemistry. Moreover, XFEL-based nonlinear radiation-matter interaction allows to probe processes and properties inaccessible before via nonlinear X-ray spectroscopies. A broad variety of X-ray pump-probe schemes can be classified by energy of the pump photons inducing vibrational (IR-pump), valence (UV-pump) or core (X-ray-pump) electron excitation and triggering complex electron-nuclear dynamics that can be effectively probed by element and site selective short X-ray pulses. In my talk I will give a brief overview of the theoretical development of various X-ray pump-probe schemes performed in our group during the last few years. I present X-ray probe of IR- and UV-induced nuclear dynamics in the framework of time-resolved X-ray absorption and more sophisticated time-resolved resonant Auger scattering and coincidence techniques, give an outlook for X-ray pump X-ray probe techniques for studying interference phenomena on electronic channels and Cohen-Fano interference in recoil-induced rotation. I will also propose a nonlinear scheme for observing XUV-induced Rabi oscillation in super fluorescence. Discussion will include experimental feasibility of various X-ray pump-probe schemes, where feedback from XFEL experts in audience is highly appreciated.
