PALP · Physics of Atoms with Attosecond Light Pulses

The field of attosecond science is now entering the second decade of its existence, with good prospects for breakthroughs in a number of areas. We want to take the next step in this development: from mastering the generation and control of attosecond pulses to breaking new marks starting with the simplest systems, atoms. The aim of the present application is to advance the emerging new research field “Ultrafast Atomic Physics”, where one- or two-electron wave packets are created by absorption of attosecond pulse(s) and analyzed or controlled by another short pulse. Our project can be divided into three parts:1. Interferometric measurements using tunable attosecond pulsesHow long time does it take for an electron to escape its potential?We will measure photoemission time delays for several atomic systems, using a tunable attosecond pulse source. This type of measurements will be extended to multiple ionization and excitation processes, using coincidence measurements to disentangle the different channels and infrared ionization for analysis.2. XUV pump/XUV probe experiments using intense attosecond pulsesHow long does it take for an atom to become an ion once a hole has been created?Using intense attosecond pulses and the possibility to do XUV pump/ XUV probe experiments, we will study the transition between nonsequential double ionization, where the photons are absorbed simultaneously and all electrons emitted at the same time and sequential ionization where electrons are emitted one at a time.3. ""Complete"" attosecond experiments using high-repetition rate attosecond pulsesWe foresee a paradigm shift in attosecond science with the new high repetition rate systems based on optical parametric chirped pulse amplification which are coming to age. We want to combine coincidence measurement with angular detection, allowing us to characterize (two-particle) electronic wave packets both in time and in momentum and to study their quantum-mechanical properties.""