Nanomechanical resonance measurement facility

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A string on a musical instrument vibrates at a characteristic resonance frequency when plucked; adding weight to the string (or choosing a thicker string) allows shift to a lower frequency, or pitch. Nanoscale resonators are strings or rods of diameter from millionths to a thousandth of a millimeter in diameter, sensitive enough to show a measurable change in resonance frequency with added weight as small as that of a few large molecules. By coating their surface to allow only specific molecules e.g. disease marker molecules, to bind, we can detect small concentrations of markers. Early detection of cancer, sensitive monitoring of disease states during treatment, as well as detection of traces of chemicals in the environment are applications with strong potential. Additionally, the stiffness and durability of new materials engineered to have different internal structure can be evaluated from the resonance frequency of small structures. Study of the resonance also allows sensitive measurement of the force due to gas molecules colliding with the resonator surface, helping the development of rarefied gas dynamics theory. This theory may be used to predict the air damping force on more complex nanostructure shapes designed for biosensors, or the trajectory of large metre-sized objects after entering the rarefied upper atmosphere.