Additive manufacturing and passive vacuum pumping for quantum devices
Work from a collaborative project involving TSL has recently been published in a peer‑reviewed journal and is already attracting attention with an online review in Physics Magazine and another in Physics World.
TSL participated in a successful Innovate UK project known as QTEAM (Quantum Technologies Enabled by Additive Manufacturing) which demonstrated the use of additive manufacturing techniques to design and produce lightweight and power‑efficient space gravimeters that use quantum properties to provide highly accurate measurements of variations in gravity. Metamorphic AM led the project, which also involved University of Nottingham and RAL Space.
These 3D surfaces are significantly more effective than a flat surface for passive pumping.
One aspect of the project was to explore the use of non-evaporable getter (NEG) coatings as passive vacuum pumps alongside a miniature sputter ion pump. Getters work by chemically reacting with gases in the system to form stable solid-phase reaction products as a means of removing them from circulation. The getter was applied by TSL as a thin-film coating that adds very little weight and once activated by heating requires no additional power to operate as a pump.
Getter coatings were applied to structured surfaces that were engineered to increase surface area and to increase the probability of reaction. The design process for the structured surfaces was carried out by Dr Nathan Cooper at University of Nottingham, using numerical simulations to maximize the interaction between the surface and impinging gas molecules. The theoretical work suggests that the structures have the potential for significant further optimization. The designs were informed by TSL’s experience of sputtering (the vacuum process used to apply the NEG coating).
A series of trials, at both TSL and University of Nottingham, confirmed that the getter coatings provided extra pumping capacity in addition to that of the ion pump.
The article is available to read in the journal Physical Review Applied and is open access so available to all with no paywall. Nottingham’s Dr Cooper is the lead author with four of the co-authors being from the technical and engineering staff at TSL.
