Attosecond Electron Dynamics in Molecular and Condensed Phase Systems

This is a programme of advanced research with potential for extremely high scientific impact and applications to areas of great strategic importance to the UK, such as renewable energy and biomolecular technology. The aim is to develop and apply a combination of cutting-edge experimental and theoretical tools to observe and model dynamics in molecules and condensed phase matter with 100 attosecond temporal and nanometre spatial resolutions. The temporal resolution we will achieve is two orders of magnitude beyond the current state-of-the-art for measurements in larger molecules and condensed matter. The history of science shows that whenever such large improvements in measurement capability occur major new breakthroughs are inevitable. For instance, it has recently emerged that sudden electronic excitation in key molecular building blocks of matter is followed by a universal primary event - sub-femtosecond to few femtosecond migration of electric charge across nanometres. This charge migration, expected to be extremely important in triggering subsequent nuclear dynamics and so controlling chemical change, is too fast to be observed with existing methods. The proposed research programme will apply the world-leading experimental and theoretical tools developed by the assembled team to study the nature of charge migration and other previously unexplored attosecond-scale processes. We will pioneer the investigation in both condensed phase matter and large molecules including the building blocks of biomolecules. The knowledge gained from this research will lead to a new understanding of the first moments in the electronic excitation of matter and ultimately to, for example, new approaches for optimising artificial light harvesting, molecular electronic devices and biomolecular analysis.Imaging and controlling dynamics of matter at the level of electrons, especially far from equilibrium, and understanding the role of quantum coherence in molecules and nanoscale assemblies have been identified by the US Department of Energy as key components of five grand scientific challenges to basic energy sciences (Phys.Today, July 2008, p28-33). Our programme will enable the concerted effort and close linking of experiment and theory needed to address these questions. The UK has a unique opportunity for world leadership in this area, as we have assembled an exceptional team that commands all of the technical and theoretical tools required to lead this new and important area of science.Our programme will exploit two new types of measurements that we have already begun to develop: high harmonic generation (HHG) spectroscopy and attosecond pump-probe spectroscopy, and will apply them to the measurement of attosecond electron dynamics in large molecules and the condensed phase. This is a formidable challenge that will open new frontiers both experimentally and theoretically. This challenge will be met by our coordinated and balanced programme that will bring together theoretical and experimental expertise in attosecond physics, quantum chemistry, molecular structure and dynamics, ultrafast and intense-field science, nanoscale and plasma physics.The programme is structured into 4 interlinked projects, each of which makes a major contribution to the eventual research outcomes: Project 1: High harmonic generation (HHG) spectroscopy Project 2: Attosecond pump-probe spectroscopy Project 3: Coupling of charge migration and nuclear dynamics Project 4: Probing attosecond dynamics in the condensed phase .

While the immediate beneficiaries of this knowledge will be academic our focus is on questions identified as key for the development of basic energy sciences over the next decades. Thus, in the intermediate term, we expect impact in a number of industrial sectors, such as renewable energy, nanotechnology devices and pharmaceuticals. The exploitable knowledge that can be forseen includes: - Characterization of the initial electronic steps in light harvesting that can be exploited to aid engineering of more efficient solar cells - Identification of the full mechanism behind the use of intense laser field scalpels as a biomolecular analysis tool with the resultant increase of fidelity and throughput - Insights into few fs electron dynamics in nanoscale objects with the possibility to develop ultrafast nanophotonic and nanoplasmonic devices for communications and information processing Aside from economic benefits there are obvious societal benefits arising from these potential outcomes (e.g. clean and efficient energy sources, medical advances). The second most important channel of economic impact (after the knowledge generated) will be the direct exploitation of the new instrumentation and software developed through this research. This instrumentation will offer advanced measurement tools that will find application across a wide range of scientific and technical activities. The categories of new instrumentation are for example: - Compact and robust short pulse light sources (applications to e.g. biomedical research, metrology) - Ultrafast optical devices and diagnostics (applications to e.g. multiple ultrafast laser technologies) - XUV absorption workstation for ultrafast measurements in a wide range of condensed samples (applications e.g. to catalysis) - Nanoscale droplet and liquid jet delivery systems (applications to e.g. biological imaging at FELs, fusion technology) - New software tools e.g. compatible with future Gaussian releases (applications to e.g. quantum chemistry) The training resulting from the programme will be of benefit to a number of staff funded directly by the programme (we anticipate > 10 individuals to be employed as PDRA's and PG's during the course of the work) and from other sources (> 10 other PG's from UK, EU and other sources) in the course of the Programme. The important skills that will be imparted are: - Ultrafast science and measurement methods - Complex quantum simulations - Advanced data analysis techniques These are highly valued skills across a broad suite of employers e.g. AWE, financial modelling, the opto-electronics and laser industries, biochemical analysis and instrumentation manufacturers, telecommunications and defence. The topic of this research - making the fastest ever measurements - is an ideal subject for the broad engagement with the public. We have found a considerable appetite for our popular presentations in the media and at the 2008 Royal Society Summer Exhibition. We believe this is an ideal area to capture public interest in science as it is at the forefront of measurement and knowledge. It is an excellent opportunity to communicate the importance and fascination of physics to a broad public, especially since mainstream physics is typically harder to sell than astronomy or particle physics where the public is much better prepared.