Perturbation of nanoparticle on deformed microcavity

Here we studied the perturbation of nanoparticles on the resonances in deformed microcavities. Owing to the breaking of rotational symmetry in deformed cavities, the field distributions are not uniform along the cavity boundary and thus result in position dependent perturbation of a single scatterer. Combined with the directional emission of deformed cavities, such perturbation provides the possibility to detect the position of nanoparticle in the far field. Our numerical example shows that a position change of the nanoparticle in 100 nm on the boundary can induce a spectral shift of ∼0.02 nm, which can be easily resolved by a conventional spectrometer.