Phonon lasing enhanced mass sensor with zeptogram resolution under ambient conditions

High-sensitivity mass sensors under ambient conditions are essential in various fields such as biological research, gas sensing and environmental monitoring. In the current work, a phonon lasing enhanced mass sensor was proposed based on an optomechanical crystal cavity under ambient conditions. The phonon lasing was harnessed to achieve ultra-high resolution since it resulted in an extremely narrow mechanical linewidth (less than 10 kHz). Masses with different weights were deposited on the cavity, it is predicted that the maximum resolution for mass sensing can be 65 ± 19 zg, which approaches the mass order of a protein and an oligonucleotide. This implies the potential application of the proposed method in the biomedical fields such as oligonucleotide drug delivery area and the Human Proteome Project.