Tipping the Scales—Just Barely

摘要

Researchers are making big strides in a race to build nano-sized devices capable of weighing a single proton. Next to Kate Moss, Michael Roukes may be the most obsessive weight watcher on Earth. Roukes, a physicist at the California Institute of Technology (Caltech) in Pasadena, isn't particularly worried about putting on or shedding a kilogram. He's thinking much lighter than that. In the 4 April issue ofNano Letters, Roukes and colleagues report making the most sensitive mechanical scale ever, capable of registering 0.000000000000000000007 grams, or 7 zeptograms.