ELFT HÍRADÓ

[mcsete AT physx.u-szeged.hu]

Meghívó

SZTE TTIK Fizikus Tanszékcsoport Szemináriuma

 Előadó: Prof. Tőkési Károly, tudományos tanácsadó
 MTA Atommagkutató Intézet, Elektronikai Osztály

 Cím: Ionization by intense and short electric pulses - classical picture

 Időpont: 2015. december 4, 12 h

 Helyszín: SZTE TTIK, Bay Zoltán tanterem, Szeged, Tisza Lajos körút. 84-86.

 Absztrakt:

We present theoretical studies of the ionization of simple targets  
like hydrogen atom, positronium and water molecule as a result of the  
interaction with an ultrashort external electric field.  
Doubly-differential momentum distributions and angular momentum  
distributions of ejected electrons calculated in the framework of the  
Coulomb-Volkov and strong field approximations, as well as classical  
calculations are compared with the exact solution of the time  
dependent Schrödinger equation. We show that in the impulsive limit,  
the Coulomb-Volkov distorted wave theory reproduces the exact  
solution. The validity of the strong field approximation is probed  
both classically and quantum mechanically.
We show that classical mechanics describes the proper quantum momentum  
distributions of the ejected electrons right after a sudden momentum  
transfer, however pronounced the differences at latter stages that  
arise during the subsequent electron-nucleus interaction. Although,  
the classical calculations reproduce the quantum momentum  
distributions, it fails to describe properly the angular momentum  
distributions, even in the limit of strong fields. The origin of this  
failure can be attributed to the difference between quantum and  
classical initial spatial distributions.
For the case of water molecule target, single active electron and  
frozen core calculations were performed within the hydrogenic  
approximation. Electrons from the highest occupied molecular orbital  
1b1 were considered. We demonstrate that the agreement between the  
classical and quantum mechanical calculation at high intensities is  
excellent, where the over-the-barrier ionization mechanism is dominant.

Minden érdeklődőt szeretettel várunk.

 Dr. Csete Mária
 szeminarium-koordinator


----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.