title: Temporal coupled-mode theory for the Fano resonance in optical resonators.
abstract: We present a theory of the Fano resonance for optical resonators, based on a temporal coupled-mode formalism. This theory is applicable to the general scheme of a single optical resonance coupled with multiple input and output ports. We show that the coupling constants in such a theory are strongly constrained by energy-conservation and time-reversal symmetry considerations. In particular, for a two-port symmetric structure, Fano-resonant line shape can be derived by using only these symmetry considerations. We validate the analysis by comparing the theoretical predictions with three-dimensional finite-difference time-domain simulations of guided resonance in photonic crystal slabs. Such a theory may prove to be useful for response-function synthesis in filter and sensor applications.
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA. shanhui@stanford.edu
authors.forename: Shanhui
authors.initials: S
authors.lastname: Fan
authors.forename: Wonjoo
authors.initials: W
authors.lastname: Suh
authors.forename: J D
authors.initials: JD
authors.lastname: Joannopoulos