Optimized cell geometry for buffer-gas-cooled molecular-beam sources
| Autor: | Daniel Gusa, Tim Ossenbrüggen, Daniel A. Horke, Igor Rubinsky, Nils Roth, Vijay Pal Singh, Jochen Küpper, Amit K. Samanta |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Chemical Physics (physics.chem-ph)
Physics Buffer gas Fluid Dynamics (physics.flu-dyn) FOS: Physical sciences chemistry.chemical_element Rotational temperature Physics - Fluid Dynamics 02 engineering and technology Conical surface 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics Spectral line Planar chemistry Physics - Chemical Physics Ionization 0103 physical sciences ddc:530 010306 general physics 0210 nano-technology Molecular beam Helium |
| Zdroj: | Physical review / A 97(3), 032704 (2018). doi:10.1103/PhysRevA.97.032704 |
| ISSN: | 2469-9934 2469-9926 |
| DOI: | 10.1103/physreva.97.032704 |
| Popis: | We have designed, constructed, and commissioned a cryogenic helium buffer-gas source for producing a cryogenically cooled molecular beam and evaluated the effect of different cell geometries on the intensity of the produced molecular beam, using ammonia as a test molecule. Planar and conical entrance and exit geometries are tested. We observe a threefold enhancement in the ${\mathrm{NH}}_{3}$ signal for a cell with planar entrance and conical-exit geometry, compared to that for a typically used ``boxlike'' geometry with planar entrance and exit. These observations are rationalized by flow field simulations for the different buffer-gas cell geometries. The full thermalization of molecules with the helium buffer gas is confirmed through rotationally resolved resonance-enhanced multiphoton ionization spectra yielding a rotational temperature of 5 K. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|