NIST Develops Quantum-Based Pressure Standard
The National Institute of Standards and Technology (NIST) has created a new quantum-based pressure standard using a Fixed Length Optical Cavity (FLOC) interferometer. This method precisely measures refractive index changes in gases, allowing for SI-traceable pressure measurements with high accuracy.
Key Points:
– FLOC uses laser-based interferometry to measure gas pressure
– Measures refractive index changes proportional to gas pressure
– Directly traceable to SI units through quantum chemistry calculations
– Operational range of 1 Pa to 300 kPa with 0.0009% uncertainty
– NIST is building infrastructure for customer calibrations
Impact:
– Replaces mercury-based pressure standards
– Enables quantum-based pressure measurements
– Improves pressure measurement accuracy
– Potential for portable commercial applications
Implementation:
– NIST currently building infrastructure and documentation
– Mercury standards to be decommissioned
– Active research projects on extending measurement range and techniques
Keywords: refractive index, Fabry-Perot interferometer, laser-based, SI-traceable, quantum-based
