Ultrafast Switching of Coherent Electronic Excitation: Great Promise for Reaction Control on the Femtosecond Time Scale

Abstract

We report on a physical mechanism of coherent control with shaped intense femtosecond laser pulses. To this end we study photoelectron spectra from the multi-photon ionization of potassium atoms using tailored femtosecond laser pulses. Our results are interpreted in terms of Selective Population of dressed states (SPODS). Two realizations of SPODS by Photon Locking and Rapid Adiabatic Passage are discussed. A physical picture of SPODS based on the interplay of the laser electric field and the atomic wave function is presented. In addition, coherent control of a larger molecule (isopropyl alcohol) by shaped femtosecond laser pulses is demonstrated experimentally.KeywordsPhotoelectron SpectrumFemtosecond Laser PulseQuantum ControlSelective PopulationPotassium AtomThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.