"On the applicability of the adiabatic theory for atomic systems in strong laser fields"

TYPESpecial Seminar - Solid State Institute, Technion
Speaker: Ms. Hanna Martiskainen
Affiliation:The Physics Department, Technion
Location:Solid State Auditorium(Entrance)
Remark:M.Sc. Student of Professor Nimord Moiseyeve
Abstract:The generation of high order harmonics is commonly described by a semi-classical three-step model (TSM). In the first step of the model the adiabatic approximation is used to evaluate the tunneling of the electron through the potential barrier.

The main goal of this work is to determine for what laser parameters (i.e. field amplitude ε0 and frequency ω) the exact photo-induced dynamics can be obtained within the framework of perturbation theory. The zeroth order Hamiltonian is the adiabatic Hamiltonian, and the perturbation is the non-adiabatic coupling. The parameter controlling the strength of this coupling is the laser frequency ω.
We introduce a method which avoids the need to calculate explicitly the high order terms in the perturbation series expansion of the solutions of the Schrӧdinger equation.
We also show how the radius of convergence of perturbation theory varies as a function of the laser intensity.