Physics Colloquium - Generation and application of attosecond pulses for real-time observation of atomic processes

Guillaume Laurent

Research Laboratory of Electronics, Massachusetts Institute of Technology

The interaction of light with matter is an essential process in nature and, in particular, the photoionization process has been studied during decades. The recent development of light pulses in the attosecond timescale (1 as =10-18 s) has opened up new avenues to probe temporal aspects of these fundamental processes in atoms, molecules, and more complex systems. This leads physicists to question some of the well-established assumptions in the field: How long does it take to remove an electron from an atom? How fast the atomic orbital rearrange after one or several electrons have been removed?

In the first part of this colloquium, I will present a broad overview of the attosecond physics science with a selection of recent highlights and give an outlook on future directions. The generation and characterization of attosecond pulses, and their application for real time observation of atomic processes will be reviewed.

In the second part, I will show how such tools can be also used to control the electron dynamics in atom on an attosecond time scale. By combining an attosecond pulse and its fundamental infrared field, we will see how a strong asymmetric emission of continuum electrons is generated along the direction of the laser polarization.