Vacuum Pressure Measurements using a Magneto-Optical Trap

TL;DR

This paper demonstrates that the loading dynamics of an alkali-atom magneto-optical trap can serve as a reliable, non-invasive method for measuring ultra-high vacuum pressure, with accuracy across various conditions.

Contribution

It introduces a method to estimate vacuum pressure using magneto-optical trap loading times, applicable over a wide pressure range and robust against different experimental parameters.

Findings

Loading time T correlates with vacuum pressure as ≤ [2x10^(-8) Torr s]/T.

Method remains accurate within a factor of two despite variations in trap parameters.

Effective in measuring pressures down to approximately 10^(-10) Torr.

Abstract

The loading dynamics of an alkali-atom magneto-optical trap can be used as a reliable measure of vacuum pressure, with loading time T indicating a pressure less than or equal to [2x10^(-8) Torr s]/T. This relation is accurate to approximately a factor of two over wide variations in trap parameters, background gas composition, or trapped alkali species. The low-pressure limit of the method does depend on the trap parameters, but typically extends to the 10^(-10) Torr range.