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

Development of techniques for cooling and trapping polar diatomic molecules

David R. Glenn

Jan 1, 20091 citation

Electrostatic Extraction of Cold Molecules from a Cryogenic Reservoir

L. D. van Buuren, Christian Sommer, M. Motsch +5 more

We present a method which delivers a continuous, high-density beam of slow and internally cold polar molecules. In our source, warm molecules are first cooled by collisions with a cryogenic helium buffer gas. Cold molecules are then extracted by means of an electrostatic quadrupole guide. For ${\mathrm{ND}}_{3}$ the source produces fluxes up to $(7{\ifmmode\pm\else\textpm\fi{}}_{4}^{7})\ifmmode\times\else\texttimes\fi{}{10}^{10}\text{ }\text{ }\mathrm{\text{molecules}}/\mathrm{s}$ with peak densities up to $(1.0{\ifmmode\pm\else\textpm\fi{}}_{0.6}^{1.0})\ifmmode\times\else\texttimes\fi{}{10}^{9}\text{ }\text{ }\mathrm{\text{molecules}}/{\mathrm{cm}}^{3}$. For ${\mathrm{H}}_{2}\mathrm{CO}$ the population of rovibrational states is monitored by depletion spectroscopy, resulting in single-state populations up to $(82\ifmmode\pm\else\textpm\fi{}10)%$.We present a method which delivers a continuous, high-density beam of slow and internally cold polar molecules. In our source, warm molecules are first cooled by collisions with a cryogenic helium buffer gas. Cold molecules are then extracted by means of an electrostatic quadrupole guide. For ${\mathrm{ND}}_{3}$ the source produces fluxes up to $(7{\ifmmode\pm\else\textpm\fi{}}_{4}^{7})\ifmmode\times\else\texttimes\fi{}{10}^{10}\text{ }\text{ }\mathrm{\text{molecules}}/\mathrm{s}$ with peak densities up to $(1.0{\ifmmode\pm\else\textpm\fi{}}_{0.6}^{1.0})\ifmmode\times\else\texttimes\fi{}{10}^{9}\text{ }\text{ }\mathrm{\text{molecules}}/{\mathrm{cm}}^{3}$. For ${\mathrm{H}}_{2}\mathrm{CO}$ the population of rovibrational states is monitored by depletion spectroscopy, resulting in single-state populations up to $(82\ifmmode\pm\else\textpm\fi{}10)%$.

arXiv:0806.2523Physical Review LettersJan 21, 200993 citations

{\mathrm{ND}}_{3}

the source produces fluxes up to $(7{\ifmmode\pm\else\textpm\fi{}}_{4}^{7})\ifmmode\times\else\texttimes\fi{}{10}^{10}\text{ }\text{ }\mathrm{\text{molecules}}/\mathrm{s}$ with peak densities up to $(1.0{\ifmmode\pm\else\textpm\fi{}}_{0.6}^{1.0})\ifmmode\times\else\texttimes\fi{}{10}^{9}\text{ }\text{ }\mathrm{\text{molecules}}/{\mathrm{cm}}^{3}$. For

{\mathrm{H}}_{2}\mathrm{CO}

the population of rovibrational states is monitored by depletion spectroscopy, resulting in single-state populations up to $(82\ifmmode\pm\else\textpm\fi{}10)%$.