Nested silicon microring resonator with multiple coupling regimes

We propose and demonstrate a nested silicon microring resonator that realizes multiple coupling regimes at different resonance wavelengths in one passive device. Resonance notches with diverse depths and bandwidths in the transmission intensity spectrum can be experimentally achieved, which demonstrates the intensity responses of multiple coupling regimes. Moreover, the phase responses of multiple coupling regimes is also verified by observing fast or slow lights at different resonance wavelengths.