World's Most Sensitive Nanomechanical Sensor Can Detect the Mass of One Proton
Posted on April 1, 2012
Researchers at ICN's Quantum NanoElectronics Group have fabricated and tested the world's most sensitive nanomechanical sensor. The sensor is capable of detecting changes in mass of 1.7 yoctograms (1.7 x 10-24 g), which is about the mass of one proton. 1 yoctogram equals 10-24 grams.
New Scientist reports that before this ultra sensitive sensor the smallest mass a sensor could detect was 100 yoctograms, which is a tenth of a zeptogram.
The sensor was built using a 150 nanometer carbon nanotube that spans a trench of similar length. An SEM image of the sensor is pictured above. The researchers describe the sensor as a being akin to a vibrating guitar string. By comparing the resonating frequency of the nanotube before and after some additional mass has been bound to the nanotube's surface, the researchers can quantify the added mass.
The research was published here in Nature Nanontechnology.