NCTS (South)



PLACER49223, Second Physics Building , NCKU

FIELDQuantum Information Science

SPEAKER Dr. Hsin-I Lu - Harvard University, USA

TITLEToward Optical Loading of CaH into a Magnetic Trap

ABSTRACTProducing cold, chemical diverse molecules in a large quantity can have a profound impact in various fields, including quantum simulation, cold, controlled chemistry, and precision measurements. Here, we report the progress toward loading a very slow CaH molecular beam into a deep magnetic trap, by employing optical pumping techniques. A cold, slow CaH beam is produced from a two-stage buffer gas cell [1] and has a forward velocity of 65 m/s (longitudinal and transverse velocity spreads are 40 m/s and 50 m/s, respectively). A hexapole magnetic lens is used to focus the molecular beam to the 4T deep magnetic trap, locating at 30 cm from the source. When the molecules reach the trap area, we plan to apply two optical pumping lasers at the saddle point and near the trap center to achieve irreversible loading and magnetic deceleration. A Monte Carlo simulation indicates this loading process can load ~0.1% of the molecules that exit the beam source into the trap. Since only a few photon scattering is needed to achieve loading, this method is applicable to a wide range of magnetic molecules, including those without closed cycling transitions. Continuously loading to build up the molecular density is feasible. We plan to co-load CaH with Li atoms to study cold CaH-Li collisions and investigate the feasibility of sympathetic cooling of CaH [2].

[1] H.-I Lu, J. Rasmussen, M. J. Wright, D. Patterson and J. M. Doyle. Phys. Chem. Chem. Phys. 13, 18986-18990 (2011). [2] T. V. Tscherbul, J. Kłos, and A. A. Buchachenko. Phys. Rev. A 84, 040701(R) (2011).