Chapter 3 - Coherence Effects in Laser-Induced Continuum Structure

Abstract

Abstract We review recent developments in coherence related phenomena involving metastable states embedded in (multiple) continua via the action of (strong) laser pulses. The role of Laser-Induced Continuum Structure (LICS) in a number of diverse phenomena, such as Coherent Population Trapping , enhancement and suppression of photo-ionization and photo-dissociation, and population transfer through manifolds of continuum states is discussed. We also discuss the effect of (natural and light induced) structured multiple continua on Electromagnetically Induced Transparency and the slowing down of light. We explore the relation of LICS to Coherent Control (CC) which makes use of interferences between several quantum pathways so as to control the branching ratios of processes involving bound-bound or bound-continuum optical transitions. As examples, we discuss the use of CC and LICS in controlling the electronic branching in the photo-dissociation of the Na 2 molecule and the photo-electron angular distribution in atoms. Finally, we discuss the Coherently Controlled Adiabatic Passage (CCAP) method, which combines the selectivity of CC with the robustness of Adiabatic Passage for executing complete population transfers from an arbitrary superposition of initial states to an arbitrary superposition of target states.