Group members:

Main direction: HHG spectroscopy of polyatomic molecules

Nonlinear interaction of intense infrared laser light with atoms or molecules converts incident radiation into its very high harmonics, increasing the frequency of the incident field by one to two orders of magnitude. This process is referred to as “high harmonic generation”. The properties of high harmonic emission – their amplitudes, phases and polarizations – encode spatial and temporal information about the participating molecules, with the potential to combine sub-femtosecond temporal and sub-Angstrom spatial resolution.
The long-term goal of our research is to turn HHG spectroscopy from exotic method into a spectroscopic tool by systematically analyzing and checking its ranges of applicability, providing theoretical foundation and techniques for reconstructing various types of electron dynamics from experimental observables.

Our short-term goals include:

• Imaging attosecond dynamics of a hole created by ionization, both during and after ionization;
  
• Time-resolving and controlling electron rearrangement upon ionization
  
• Time-resolving and controlling the autoionization dynamics
  

Theoretical ambitions include understanding and modeling of

• Static and quasi-static Stark-shifts and tunnelling ionization rates in polyatomic molecules;
  
• Laser-induced non-adiabatic multi-electron excitations in the neutral, including excitation of charge transfer and autoionizing states, which open new ionization pathways;
  
• Coupling of multiple ionization continua in atoms and molecules during ionization;
  
• Modelling and reconstructing multi-electron dynamics on the sub optical cycle time-scale.
  
• Electron-molecule scattering in strong laser fields
  
• Role of electron-ion entanglement in detecting hole dynamics
  
• Decoupling temporal and spatial information in harmonic spectra
  

Our recent publications include:

O. Smirnova, Y. Mairesse, S. Patchkovskii, N. Dudovich, D. Villeneuve, P. Corkum and M. Y. Ivanov, High harmonic interferometry of multi-electron dynamics in molecules, Nature 460, 972-977 (2009).

O. Smirnova, S. Patchkovskii, Y. Mairesse, N.Dudovich and M.Y.Ivanov, Strong-field control and spectroscopy of attosecond electron-hole dynamics in molecules, Proc. Natl. Acad. Sci. U.S.A. 106, 16556-16561 (2009) .

Olga Smirnova, Serguei Patchkovskii, Yann Mairesse, Nirit Dudovich, David Villeneuve, Paul Corkum, and Misha Yu. Ivanov, Attosecond Circular Dichroism Spectroscopy of Polyatomic Molecules, Phys. Rev. Lett. 102, 063601 (2009)