Figure 6.
Mode-Splitting Sensing Enhancement Mechanisms
(A) Self-heterodyned microlaser detection of a single nanoparticle.32 (i) Before nanoparticles arrive, a single mode appears in the lasing spectrum and the laser intensity is constant. (ii) The lasing mode splits into two modes when the first nanoparticle binds, leading to a beat note at a frequency that is equal to the frequency difference between the two modes. (iii) The lasing spectrum and the frequency of the beat note change again when a second nanoparticle binds.
(B) Sensitivity enhancement at exceptional points.48