This thesis reports on the combination of buffer-gas cooling with electric velocity filtering to produce a high-density guided beam of slow and internally cold polar molecules. In the continuous source, warm molecules are first cooled by collisions with a cryogenic helium buffer gas. Cold molecules are then extracted by means of an electric quadrupole guide. For formaldehyde the population of individual rotational states in the guide is monitored by depletion spectroscopy, resulting in single-state populations up to 82 %. This thesis also reports on a technique to produce pulses of slow guided molecules. The pulses exhibit a narrow velocity distribution around a tunable velocity.This thesis reports on the combination of buffer-gas cooling with electric velocity filtering to produce a high-density guided beam of slow and internally cold polar molecules. In the continuous source, warm molecules are first cooled by collisions with a cryogenic helium buffer gas. Cold molecules are then extracted by means of an electric quadrupole guide. For formaldehyde the population of individual rotational states in the guide is monitored by depletion spectroscopy, resulting in single-state populations up to 82 %. This thesis also reports on a technique to produce pulses of slow guided molecules. The pulses exhibit a narrow velocity distribution around a tunable velocity.

Jan 1, 20110 citations

Cold Polar Molecules and Applications

John M. Doyle

Bulletin of the American Physical SocietyMay 30, 20080 citations

Guiding slow polar molecules with a charged wire

M. Strebel, Steffen Spieler, Frank Stienkemeier +1 more

We demonstrate experimentally the guiding of cold and slow ND ${}_{3}$ molecules along a thin charged wire over a distance of $\ensuremath{\sim}0.34$ m through an entire molecular beam apparatus. Trajectory simulations confirm that both linear and quadratic high-field-seeking Stark states can be efficiently guided from the beam source up to the detector. A density enhancement up to a factor 7 is reached for beams with velocities ranging down to $\ensuremath{\sim}150\phantom{\rule{0.28em}{0ex}}$m/s generated by the rotating nozzle technique.We demonstrate experimentally the guiding of cold and slow ND${}_{3}$ molecules along a thin charged wire over a distance of $\ensuremath{\sim}0.34$ m through an entire molecular beam apparatus. Trajectory simulations confirm that both linear and quadratic high-field-seeking Stark states can be efficiently guided from the beam source up to the detector. A density enhancement up to a factor 7 is reached for beams with velocities ranging down to $\ensuremath{\sim}150\phantom{\rule{0.28em}{0ex}}$m/s generated by the rotating nozzle technique.

arXiv:1108.2136Physical Review ANov 23, 201110 citations

Improved setup for producing slow beams of cold molecules using a rotating nozzle

M. Strebel, Frank Stienkemeier, Marcel Carto Constantin Mudrich

Intense beams of cold and slow molecules are produced by supersonic expansion out of a rapidly rotating nozzle, as first demonstrated by M. Gupta and D. Herschbach [J. Phys. Chem. A 103, 10670 (1999); 105, 1626 (2001)]. An improved setup is presented that is able to accelerate or decelerate cold atomic and molecular beams by up to 500 m/s. Technical improvements are discussed and beam parameters are characterized by detailed analysis of time-of-flight density distributions. The possibility of combining this beam source with electrostatic fields for guiding polar molecules is demonstrated.Intense beams of cold and slow molecules are produced by supersonic expansion out of a rapidly rotating nozzle, as first demonstrated by M. Gupta and D. Herschbach [J. Phys. Chem. A 103, 10670 (1999); 105, 1626 (2001)]. An improved setup is presented that is able to accelerate or decelerate cold atomic and molecular beams by up to 500 m/s. Technical improvements are discussed and beam parameters are characterized by detailed analysis of time-of-flight density distributions. The possibility of combining this beam source with electrostatic fields for guiding polar molecules is demonstrated.

arXiv:0910.3278Physical Review AMar 17, 201038 citations

A High Phase-Space-Density Gas of Polar Molecules in the Rovibrational Ground State

Kang-Kuen Ni, Silke Ospelkaus, Marcio H. G. de Miranda +7 more

Aug 21, 20085 citations

We demonstrate experimentally the guiding of cold and slow ND

{}_{3}

molecules along a thin charged wire over a distance of $\ensuremath{\sim}0.34$ m through an entire molecular beam apparatus. Trajectory simulations confirm that both linear and quadratic high-field-seeking Stark states can be efficiently guided from the beam source up to the detector. A density enhancement up to a factor 7 is reached for beams with velocities ranging down to $\ensuremath{\sim}150\phantom{\rule{0.28em}{0ex}}$m/s generated by the rotating nozzle technique.