Final Activity Report Summary - APT CHARACTERISATION (Characterisation and Tailoring of Attosecond Pulse Trains for Applications)
The project focussed on the generation, characterisation and potential applications of femtosecond and attosecond extreme ultraviolet (XUV) pulses.
When intense light from a short-pulse laser interacts with atoms or ions it generates new frequencies of radiation that are multiples of the fundamental frequency. This is called harmonic generation. Harmonics can be generated up to very high orders, corresponding to photon energies higher than 500 eV. This phenomenon is of great basic research interest, as it probes the behaviour of an atom strongly perturbed by an electromagnetic field. Moreover, the harmonic radiation is an extremely promising short-pulse and coherent source of radiation in the XUV and soft X-ray range.
One goal of the research project was to generate attosecond pulses, to characterise them in time and space and to explore their applications. 'Attophysics' is a new field of research where attosecond pulses can be used to probe dynamical processes in matter with an unprecedented time resolution. The duration of attosecond pulses is of the same order of magnitude as the classical orbit time for a ground-state electron in a hydrogen atom. These pulses should allow scientists to study the electronic motion in atoms or molecules in their ground state, inner-shell electron relaxation processes, ultrafast nuclear motions in molecules, time-resolved X-ray absorption in solids etc. The project was of the nature of fundamental research in both optics and atomic physics, with a high potential scientific impact.
Scientific achievements that were made during this project included complete characterisation of an attosecond pulse train, tailoring the properties of the attosecond pulses, confining the number of pulses in the train using time-gating or laser pulse compression techniques and application of attosecond pulse trains for studying strong-field processes.
When intense light from a short-pulse laser interacts with atoms or ions it generates new frequencies of radiation that are multiples of the fundamental frequency. This is called harmonic generation. Harmonics can be generated up to very high orders, corresponding to photon energies higher than 500 eV. This phenomenon is of great basic research interest, as it probes the behaviour of an atom strongly perturbed by an electromagnetic field. Moreover, the harmonic radiation is an extremely promising short-pulse and coherent source of radiation in the XUV and soft X-ray range.
One goal of the research project was to generate attosecond pulses, to characterise them in time and space and to explore their applications. 'Attophysics' is a new field of research where attosecond pulses can be used to probe dynamical processes in matter with an unprecedented time resolution. The duration of attosecond pulses is of the same order of magnitude as the classical orbit time for a ground-state electron in a hydrogen atom. These pulses should allow scientists to study the electronic motion in atoms or molecules in their ground state, inner-shell electron relaxation processes, ultrafast nuclear motions in molecules, time-resolved X-ray absorption in solids etc. The project was of the nature of fundamental research in both optics and atomic physics, with a high potential scientific impact.
Scientific achievements that were made during this project included complete characterisation of an attosecond pulse train, tailoring the properties of the attosecond pulses, confining the number of pulses in the train using time-gating or laser pulse compression techniques and application of attosecond pulse trains for studying strong-field processes.