Schedule Mar 15, 2013
Lens Effect for the J=0 Rotational Ground State of CH3CN by the Microwave AC Dipole Force
Takamasa Momose (UBC)

Takamasa Momose, Wei Zhong, Pavle Djuricanin (UBC, Canada)

Steffen Spieler, Frank Stienkemeier (Freiburg, Germany)

\tDirect cooling of molecules from room temperature is essential for the study of a variety of cold collisions and reactions. However, it is still a challenge to make cold molecules in the J=0 rotational ground state despite the fact that the rotational ground state is of great interest in many applications. Here, we report that the manipulation of the translational motion of a polar molecule in its rotational ground state is realized by the microwave (MW) dipole force combined with a counter-rotating nozzle. A cold molecular beam of CH3CN seeded in Kr with the longitudinal velocity of about 100 m s-1 was created by a pulsed counter-rotating nozzle.  The cold beam was then introduced into a cylindrical MW cavity, in which a standing wave, TM01p mode MW field, nearly resonant to the J=1?0 rotational transition of CH3CN was created.   By choosing an appropriate MW frequency, we successfully observed focusing and deflection of the cold beam of CH3CN due to the lens effect of the MW standing wave. The present result shows that it is possible to decelerate and trap room-temperature polar molecules in the rotational ground state by the MW dipole force. 

Author entry (protected)