Accurate, precise pressure sensing with tethered optomechanics

We show that optomechanical pressure sensors with characterized density and thickness can achieve uncertainty as low as $1.1\phantom{\rule{0.1em}{0ex}}\mathrm{%}$ via comparison with a secondary pressure standard. The agreement between the secondary standard and our optomechanical sensors is a necessary step toward using optomechanical devices as primary pressure sensors. Our silicon nitride and silicon carbide sensors are short-term and long-term stable, displaying Allan deviations compatible with better than $1\phantom{\rule{0.1em}{0ex}}\mathrm{%}$ precision and baseline drift significantly lower than the secondary standard. Our measurements also yield the in situ thin-film density of our sensors with $1\phantom{\rule{0.1em}{0ex}}\mathrm{%}$ total uncertainty or lower, aiding development of other optomechanical sensors. Our results demonstrate that optomechanical pressure sensors can achieve accuracy, precision, and drift sufficient to replace high-performance legacy pressure gauges.