Ultrafast Quantum Control of Electrons, Atoms, and Molecules

Speaker:Prof. Philip H. Bucksbaum (Stanford University)

Time and Date: 15:30- , Nov. 12, 2014

Place: Student Square Floor 1, Guanghua Tower, Handan Campus

 

 

Abstract

The time scale for internal motion in atoms and small molecules is determined by their Angstrom sizes and Rydberg binding energies to be femtoseconds or shorter. The binding fields for the outermost electrons are tens of volts per Angstrom, while inner electrons can be bound by kilovolts or more, with motion measured in attoseconds. I will describe recent experiments and new concepts designed to help us to understand the interaction of electrons, atoms and molecules utilizing laser fields on these scales of time, photon energy and field strength. Two kinds of laser sources are employed: Strong focused infrared lasers create these extreme conditions within a single optical cycle, and thereby induce atomic phenomena that evolve during fractions of a femtosecond. This is the regime of high harmonic generation and above-threshold ionization. X-ray free electron lasers can also produce these extreme fields, but at much higher oscillation frequencies. This is the regime of rapid inner shell ionization and Auger relaxation. Both types of strong-field phenomena induce dynamics on femtosecond or faster time scales. Our research seeks to understand this motion and reveal the underlying internal mechanisms responsible for it.

 

 

Biography

Stanford University and SLAC National Accelerator Laboratory, USA Phil Bucksbaum received his A.B. degree in physics from Harvard University in 1975, and his Ph.D. in physics from the University of California, Berkeley in 1980. Following a postdoctoral year at Lawrence Berkeley Laboratory, he joined the staff of Bell Telephone Laboratories in New Jersey, first as a postdoc at Holmdel, and later as a member of the technical staff at Murray Hill. He was appointed professor of physics at the University of Michigan in 1990, where he became the Otto Laporte Collegiate Professor in 1998 and the Peter Franken University Professor in 2005. In 2006, Bucksbaum moved to the SLAC National Accelerator Laboratory and Stanford University, and in 2009, he became the Marguerite Blake Wilbur Professor in Natural Science. He has joint appointments in the Physics Department, the Applied Physics Department, and the SLAC Photon Sciences Department, and he served as department chair of Photon Science (2007–2010). He is the director of the Stanford PULSE Institute for Ultrafast Science, and he also directs the Chemical Sciences Research Division at SLAC. Additionally, Bucksbaum has more than 200 publications. He has contributed to several areas of atomic physics and ultrafast science, including strong-field laser-atom interactions, Rydberg wave packets, ultrafast quantum control, and ultrafast X-ray physics.