School Seminar Program
From Femto-Chemistry to Atto-Physics: Time Resolved Atomic Reactions
Professor Anatoli Kheifets
Atomic and Molecular Physics Laboratory
The idea of using femto-second (1fs = 10-15 s) laser pulses as a strobe for studying nuclear dynamics in molecules brought a Nobel Prize in Chemistry to Ahmed Zewail in 1999 and laid the foundation of a rapidly developing field of femto-chemistry. The electronic motion in atoms and molecules, which typically occurs within tens to hundreds of atto-seconds (1as = 10-18 s), remained unexplored by this technique due to the fundamental limit in time resolution. This limit fell with the recent invention of the so-called “atto-second streak camera”. The camera makes use of the high harmonic generation process which converts a driving near-infrared femto-second pulse into coherent extreme ultraviolet bursts, at least one order of magnitude shorter than can be produced by conventional laser systems.
This novel experimental technique, when added with advanced quantum-mechanical modeling, allows one to formulate and meaningfully answer the whole range of fundamental questions which would have seemed rather scholastic merely a decade ago.
This talk aims to give a brief introduction to the ultrafast atomic phenomena and give few examples where connection with conventional atomic collision physics can be made. These include the Levinson theorem, that governs the elastic scattering phase shifts, and the inter-shell correlation in atomic photoionization.
Anatoli Kheifets obtained his PhD in 1986 from the Ioffe Institute in St. Petersburg, Russia. His dissertation was on many-electron correlation effects in atomic ionization. In 1991 he moved to Australia to join the Electronic Structure of Materials Centre at the Flinders University in Adelaide. There he laid the theoretical foundation to the new emerging field of electron momentum spectroscopy of solids. In 1997, the ESM group became part of Atomic and Molecular Physics Laboratories at RSPE-ANU. Here he continued to work on physics of many-electron systems in gas phase and condensed matter. In 2004 this work was recognized by his election to the Fellowship of the American Physical Society, and in 2005 to the Professorship at ANU. Current research interests of Anatoli Kheifets include interaction of matter with strong laser fields and ultrafast atomic phenomena.
Refreshments will be served in the Tea Room after the Seminar (around 5pm)