Descrizione del progetto
Un innovativo ed efficiente imaging a campo lontano per studi su scala nanometrica
I processi su scala nanometrica sono di particolare interesse scientifico in diversi campi, dalla biologia alla chimica e non solo. Comprenderne meglio il funzionamento potrebbe offrire un’ampia gamma di vantaggi. Nessuna tecnica di imaging a campo lontano è purtroppo in grado di studiare efficacemente le funzioni su scala nanometrica, poiché la risoluzione temporale o spaziale è inadeguata per lo studio. Il progetto HIGH-Q, finanziato dall’UE, elaborerà un’innovativa tecnica di imaging a campo lontano utilizzando impulsi laser a elettroni liberi a raggi X, imaging diffrattivo coerente ultraveloce, raggi X ultraveloci e algoritmi di ricostruzione che consentiranno uno studio efficiente dei processi su scala nanometrica. Questo progetto consentirà di dare grande impulso scientifico agli studi, fra gli altri, di fotochimica, scienze dei materiali e catalisi.
Obiettivo
Our ability to observe processes and study function at the nanoscale is hindered by the compromise between temporal and spatial resolutions inherent to the majority of far-field imaging techniques. This limits our perspective on a wide range of non-equilibrium processes at the nanoscale such as chemical/catalytic reactions, ultrafast phase-transitions and biological processes at room temperature in native phase. Intense and spatially coherent femtosecond-short X-ray flashes from free-electron laser (XFEL) sources can combine high spatial and temporal resolutions through 'diffraction-before-destruction' coherent diffractive imaging (CDI) of individual nano-specimens within a single exposure. XFEL CDI studies have found surprising variety of morphologies in soot, unknown metastable shapes of metal nanoparticles and exotic states of water, which are otherwise inaccessible. PI and colleagues applied this technique to follow an ultrafast irreversible laser-superheating process with few nanometers spatial and 100 femtosecond temporal resolutions at the single nanoparticle level.
Despite significant efforts, the spatial resolution of single XFEL CDI images of non-periodic specimen could not be improved beyond few nanometers. This proposal will overcome this limit by exploiting previously little explored phenomena which arise when specimen are exposed to newly available intense 500 attosecond to few femtosecond short FEL pulses. All matter exposed to intense X-rays is photo-ionised. When XFEL pulses are comparable or shorter than subsequent relaxation processes, non-linear effects such as transient resonances and resonant stimulated emission increase the brightness of images by several orders of magnitudes and significantly improve the spatial resolution. In combination with sparsity based reconstruction algorithms this proposal will push ultrafast CDI towards the single macromolecule limit and open novel avenues for photochemistry, catalysis, and material studies.
Campo scientifico
Parole chiave
Programma(i)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Argomento(i)
Meccanismo di finanziamento
HORIZON-ERC - HORIZON ERC GrantsIstituzione ospitante
20148 Hamburg
Germania