Paper VT-MoM4
Fundamental Quantum-based Vacuum Metrology at NIST

Monday, October 22, 2018, 9:20 am, Room 203B

NIST has developed and characterized a variety of vacuum standards over the last several decades. Much effort, particularly recently, has been placed into developing standards based on optical methods and fundamental quantum properties. In this talk, I will present an overview of these efforts, focusing on the more recent advances in vacuum metrology. These span a wide range of pressures and employ a variety of nascent methods. However, our most recent methods focus on developing absolute standard based on fundamental physical properties, particularly quantum properties. At the low vacuum, we probe the pressure-dependent index of refraction of a gas in a fixed-length optical cavity (FLOC). At the middle range from the viscous flow regime to the high vacuum, we relate the ring-down time of a membrane to pressure (“Brane” gauge). At the ultra and extreme high vacuum (UHV and XHV), we use the loss-rate of ultra-cold atoms from a magnetic trap to measure background particle energy density in the cold-atom vacuum standard (CAVS). Each of these techniques presents unique technical challenges, I will put these challenges in context and briefly describe the research ongoing to address them. These include techniques to measure the refractivity of gases and distortion characterization for the FLOC, optomechanics and nanophotonics for the Brane gauge, and collision cross section measurements for the CAVS.