LAUSR

We propose a mass sensor using optically trapped and cooled dielectric microdisks. The center-of-mass motion of a trapped particle in vacuum can experience extremely low dissipation resulting in robust decoupling from the heat bath. It leads to a long heating time thus the measurement can be accomplished before a jump in the phonon number without the optomechanical cooling. This method can lead to milli-dalton mass sensitivity which approximates to the mass of one electron.