Deceleration and cooling of large molecules using time-varying electric fields

• Applicant: Professor Dr. Jochen Küpper
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2003 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5407322

In this project we propose to develop the techniques to cool and store large molecules and biomolecules at ultra-low temperatures in the gas-phase to allow for precision spectroscopy of such systems. The cooling of the molecules will be performed by supersonic co-expansion of the molecules seeded in rare-gases and successive slowing of the molecules using time-varying electric fields, exploiting their Stark effects. The molecules will be slowed down to velocities that allow their storage in electrostatic traps or rings. The storage of large molecules and biomolecules at very low temperatures will allow for ultra-high resolution studies of the physical and chemical properties of such systems. We propose to employ, develop, or extend the techniques needed to transfer such large molecules into the gas-phase, decelerate, store, and detect them using benzonitrile (BN) as a test-case. BN has a molecular mass comparable to small biomolecules such as DNA-bases, amino acids, and small di- and oligo-peptides, and thus will be an excellent model for such systems. Moreover, being a relatively symmetric asymmetric top, BN is an interesting molecule for ultra-high resolution spectroscopy in the UV-, IR-, and MW-frequency range.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1116: Interactions in ultracold and molecular gases