Atomic & Molecular Physics

With each breath, humans exhale more than 1,000 distinct molecules, producing a unique chemical fingerprint or “breathprint” rich with clues about what’s going on inside the body. For decades, scientists have sought to harness that information, turning to dogs, rats and even bees to literally sniff out cancer, diabetes, tuberculosis and more. This week, scientists from the University of Colorado Boulder and the National Institute of Standards and Technology (NIST) made an important leap forward in the quest to diagnose disease using exhaled breath, reporting that a new laser-based breathalyzer powered by artificial intelligence (AI) can detect COVID-19 in real-time with excellent accuracy.

Mechanical resonators featuring large tensile stress have enabled a range of experiments in quantum optomechanics and precision sensing. Many sensing applications require functionalizing tensioned resonators by appending additional mass to them. However, this may dramatically change the resonator mode quality factor, and hence its sensitivity.

In our work published in Physical Review Applied, we study how mode quality factor depends on suspending a mass on a type of membrane resonator known as a trampoline.  Surprisingly, the quality factor becomes independent of the mass in the large-load regime, for any tensioned resonator, which explains previous related results and will enable new design perspectives.