Comparing field ionization models in simulations of laser-matter interaction Marco Garten
Motivation Bohr model H-atom orbital period: 150 as distance from target surface [nm] time [as] laser intensity [W/cm²] p+p+ e-e-
Ionization Effects Collisional – Inside the target foil Multiphoton – Rare process compared to field ionization Field Ionization – Main ionization effect at the pulse front
Multiphoton Ionization
Field Ionization
Field Ionization Models Most important point: – QUASI-STATIC potential ansatz – Leute, so wirds bisher gemacht, aber das gibt große Probleme!
Landau-Lifshitz
Keldysh
BSI-extended ADK
E-dependency Am DRACO Kontrastprofil zeigen – ns, ps, fs-Skala Skin-Tiefe
Charge state evolution Gas target, oscillating field Great differences!
Typical target Picture of the typical target – Argon gas (1\mu) before and after foil – HCO – 50nm carbohydrate layer – 1\mu titanium layer
Z-dependency Large differences!
Conclusion Bisher keine kurzen pulse möglich, aber seit einiger zeit kurze hochintensive pulse! Haben gesehen, dass durch zeitliche und räumliche riesige gradienten, große unterschiede in den vorhersagen der modelle auftreten.
Outlook