Rb/Csvalues describe: SAES dispenser
Quantum hardware
Why it wins
Cold atom physics runs on a controlled trickle of Rb or Cs: chromate-plus-reducer dispensers release clean alkali vapor on current command inside sealed cells and MOT chambers.
Why not the alternative
Bulk alkali ampoules flood systems and corrode; getters alone cannot source the species.
Watch out
Activation current windows are narrow: overdrive once, contaminate forever.
Properties
The values below are candidate: compiled from the sources named, not yet individually validated.
Provisional provenance: SAES Getters datasheets and NEG literature.
Wet cleaning
| Recipe | never: the dispenser arrives sealed and is installed dry, gloves and dry N₂ |
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| Forbidden | moisture and air, which oxidise the charge before you ever use it |
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| Limit | the alkali metal itself; there is no cleaning step |
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Vacuum and outgassing
| Outgassing, unbaked (10 h) | releases by design |
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| Vapour pressure | the entire function: Rb reaches 1e-7 mbar at 40 °C |
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Temperature
| Bake, assembled | 150 °C |
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| Metallurgical limit | activation by resistive heating, 550–800 °C at the dispenser |
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Thermal
| Melting / softening | Rb 39, Cs 28 °C |
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Engineering
| Corrosion | violently reactive with water |
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| Joining | spot welded to feedthrough pins |
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| Process notes | the system bake must stay below the release temperature or you waste the charge |
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| Availability and cost | SAES |
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Grades
| SAES AMD Rb / Cs dispensers | the standard cold atom source |
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| Getter-integrated dispensers | source plus pump in sealed miniature cells |
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Sources · 1
- SAES Getters dispenser data
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