Manoram Agarwal has successfully defended his PhD thesis titled “GASFIR: General Approximator for Strong Field Ionization Rates”.
When an intense laser pulse ionizes an atom, there is no single moment at which the electron becomes free. It makes the familiar idea of an “ionization rate” surprisingly ambiguous in ultrafast strong field regime.
In his dissertation, Manoram introduces GASFIR (General Approximator for Strong-Field Ionization Rates), a semi-empirical model that captures how ionization builds up within a few-cycle pulse, combining the accuracy of numerical simulations with the speed and transparency of analytical formulas, for both atoms and solids. It constructs a rate that mirrors the physical reality of the field driving the electron out and back within a single cycle – what happens at one moment depends on the field before and after it. GASFIR shows that with the right functional constraints, sensible sub-cycle ionization rates can be recovered from nothing more than the driving fields and their resulting ionization probabilities.
Congratulations!
Picture: Nina Beier
