So, in addition to scales that can weigh single protein molecules to an accuracy of a few hundred times the mass of a proton, we now have a position sensor that can detect changes in displacement as small as 1/30,000th of the diameter of a single carbon atom, or about the diameter of a single carbon nucleus.

Houxun Miao, Kartik Srinivasan, and Vladimir Aksyuk (researchers at the National Institute of Standards and Technology’s Center for Nanoscale Science and Technology) have built a microelectromechanical system (MEMS) that pushes the lower limits of distance and force measurement down to within a short hail of the theoretical limits—to 2.3 times the standard quantum limit. [read more..]