给出了有损串联双微环谐振器的传输谱线和归一化延迟的解析表述,研究了耦合系数以及损耗对传输谱线和归一化延迟的影响。解析研究表明,在一定的耦合系数和损耗条件下,传输谱线和归一化延迟均出现双谐振峰的特征,但二者的归一化谐振频率并不重合。增大环波导耦合系数(或减小环环耦合系数),传输谱线和归一化延迟由非简并态演化为简并态,并且归一化延迟达到简并态时的环波导耦合系数要大(或环环耦合系数要小)。当损耗增大,传输谱线和归一化延迟也由非简并态向简并态逐渐演化。传输谱线的半峰全宽和归一化延迟3 dB带宽随着耦合系数或损耗的增大而增大。

Analytical expressions of transmission spectra and normalized delays of lossy series cascaded dual microring resonators are developed. The effects of coupling coefficients and losses on transmission spectra and normalized delays are discussed. The analytical study shows that dual resonance peaks are existent under specified coupling coefficients and losses. However,normalized resonance frequencies of transmission spectra and normalized delays are not identical. Increasing the ring-waveguide coupling coefficient (or decreasing the ring-ring coupling coefficient) results in the evolutions of transmission spectra and normalized delays from the non-degenerated state to the degenerated state. However,the ring-waveguide coupling coefficient of normalized delays at the degenerated state is larger or the ring-ring coupling coefficient is smaller,compared to that of transmission spectra. As the loss increases,the transmission spectra and normalized delays also develop from the non-degenerated state to the degenerated state. The full-width at half maximum of transmission spectra and 3 dB bandwidth of normalized delays both increase as the coupling coefficients and the losses increase.