Nuclear spin-selective rotational dynamics of polyatomic molecules

• Applicant: Privatdozentin Monika Leibscher, Ph.D.
• Co-Applicants: Professor Dr. Ilya Averbukh; Professor Dr. Yehiam Prior
• Subject Area: Theoretical Chemistry: Electronic Structure, Dynamics, Simulation
• Term: from 2011 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 204087927

• Final Report Year: 2016

Final Report Abstract

In this project, we have succeeded in developing methods to control rotational dynamics with laser pulses, focusing on nuclear spin selective control. In particular, we have developed schemes for excitation of uni-directional rotation. In our experiments, uni-directional molecular spinning was for the first time observed by exploiting the rotational Doppler shift. Moreover, we have investigated phenomena like quantum resonances, alignment/orientation echoes and magneto-optical birefringence. We have applied some of the methods for nuclear spin selective control of rotational dynamics to reactive atom-diatom scattering. Another important part of this project was to investigate the coupled rotational-torsional dynamics of non-rigid molecules and the resulting torsional alignment. We have extended previous two-dimensional models to a fully four-dimensional treatment of laser induced rotational-torsional dynamics. Finally we point out, that a symmetry adapted description of nuclear spin isomers has applications in other fields as well, namely for photo-chemical processes involving intra-molecular torsions. Summarizing, this was a very successful project with many theoretical and experimental outcomes. It has already opened new directions of studies in a number of research groups around the world.

Publications

• Nuclear spin selective laser control of rotational and torsional dynamics. J. Chem. Phys. 136, 084309 (2012)
  J. Floß, T. Grohmann, M. Leibscher, and T. Seideman
  
• Quantum resonance, Anderson localization, and selective manipulations in molecular mixtures by ultrashort laser pulses, Phys. Rev. A 86, 021401(R) (2012)
  J. Floß, I.Sh. Averbukh
  
• Quantum Resonances in Selective Rotational Excitation of Molecules with a Sequence of Ultrashort Laser Pulses, Phys. Rev. Lett. 109, 043003(2012)
  S. Zhdanovich, C. Bloomquist, J. Floß, I.Sh. Averbukh, J.W. Hepburn, and V. Milner
  
• Observing Molecular Spinning via the Rotational Doppler Effect, Nature Photonics, v.7, 711-714 (2013)
  O. Korech, U. Steinitz, R. J. Gordon, I. Sh. Averbukh, and Y. Prior
  
• Reactive scattering dynamics of rotational wavepackets: A case study using the model H + H2 and F + H2 reactions with aligned and antialigned H2, J. Chem. Phys. 139, 104315 (2013)
  C. J. Eyles, M. Leibscher
  
• Optics of a Gas of Coherently Spinning Molecules, Phys. Rev. Lett. 112, 013004 (2014)
  U. Steinitz, Y. Prior, and I. Sh. Averbukh
  
• Atom-diatom scattering dynamics of spinning molecules, J. Chem. Phys. 142, 024311 (2015)
  C. J. Eyles, J. Floß, I. Sh. Averbukh, and M. Leibscher
  
• Magneto-optical properties of paramagnetic superrotors, Phys.Rev.Lett. 115,033005 (2015)
  A. Milner, A. Korobenko, J. Floß, I.Sh. Averbukh, V. Milner
  
• Observation of Bloch oscillations in molecular rotation, Phys. Rev. Lett. 115, 203002 (2015)
  J. Floß, A. Kamalov, I. Sh. Averbukh, and P. H. Bucksbaum