Researchers at the University of California at Berkeley (UCB) have developed a tunable, nanotube resonator that could lead to exquisitely sensitive and versatile sensors. Nanoresonators are tiny vibrating beams, bridges or other structures. Because their resonant frequencies are highly dependent on various factors, such as their mass, length, and the stresses they are experiencing, nanoresonators make extremely sensitive measurement devices.
The UCB nanoresonators, however, are tunable because they are made of telescoping nanotubes that can extend like a trombone slide. By securing the telescoping nanotubes between two surfaces that can be moved relative to each other, the researchers were able to vary the nanoresonator frequencies over ranges of 50 to 75 megahertz. Each nanometer change in length leads to roughly a 1 megahertz shift in frequency