Sunday, February 17, 2013
Room 306 (Hynes Convention Center)
A fundamental goal of attosecond science is to image and control electronic motion in matter on its natural time scale – that of attoseconds (1 as = 10-18 sec). To image electronic changes in matter requires attosecond light pulses of high energy, i.e., with short wavelengths comparable to the scale of the electronic motions. To control electronic changes in matter requires attosecond light pulses of high intensity so that it becomes experimentally feasible to not only initiate such electronic changes with an attosecond pulse, but also to probe or alter those changes with a second pulse. Alternatively, intense few-cycle attosecond pulses can be used to control electronic processes by varying the waveform of the electric field within each pulse.
A major means of producing attosecond pulses is by high-order harmonic generation (HHG), which results from the highly non-linear interaction of an intense infrared driving laser field with an atomic or molecular gas. Consequently theorists have focused on the accurate description of HHG in order to explore ways to increase both the energy and the intensity of the harmonics used to produce attosecond pulses as well as to control the duration of the pulses. This talk will outline current theoretical understanding of HHG, with an emphasis on implications for achieving the goals of attosecond science. Potential applications of intense, few-cycle attosecond pulses to controlling electronic processes in atoms will also be presented.