Optical analogue of double Fano resonance via dressed twin continua

A semiclassical model consisting of two noninteracting waveguide arrays along with three side-coupled waveguides is presented to demonstrate the optical analogue of double Fano resonance. The photonic system is configured so that it causes simultaneous cross coupling between two decay channels via one array and another two decay channels via the other array. Owing to the two individual interference effects, the decay-rate profile for the waveguide coupled directly to the continuum exhibits two asymmetric peaks, or dips, or a combination of one peak and one dip in the vicinity of the frequency mismatches. As far as the distribution of optical field amplitudes in the side-coupled waveguides is concerned, the present model also demonstrates the features of optical trapping (optical analogue of coherent population trapping) in side-coupled waveguides under certain symmetric parametric conditions.