The storage ring contains an ultra-high vacuum of 10 mbar.

This is because diffusion pumps have the ability to create both high and ultra-high vacuum.

Note that in other fields, a lower division between high and ultra-high vacuum is common, often 10 Pa.

The vacuum level inside the tube is ultra-high vacuum on the order of 0.01 Pa to 133 nPa.

This also illustrates why ultra-high vacuum must be used to study solid-state surfaces, nanostructures or even single molecules.

Chen, et al. doped graphene with potassium in ultra-high vacuum at low temperature.

Gold wire is used as a gasket in demountable seals for ultra-high vacuum.

There is no single vacuum pump that can operate all the way from atmospheric pressure to ultra-high vacuum.

Molecular beam epitaxy takes place in high vacuum or ultra-high vacuum (10 Pa).

High to ultra-high vacuum removes the obstruction of air, allowing particle beams to deposit or remove materials without contamination.