  Light trapping and radiation process from linear reciprocal photonic
resonators is one of the fundamental processes in optical science and
engineering. Recently, the concept of coherent virtual absorption (CVA) of
light was introduced and investigated for planar and cylindrical optical
structures. The key feature of CVA is that by engineering the time-dependence
of the excitation waveform, one can temporarily store all the input energy into
the optical structure without any leakage. Here we further explore this novel
concept in integrated photonic setups made of microring resonators. By using
coupled-mode theory (CMT), we derive an analytical expression for CVA in this
platform. This in turn allows us to make the connection with the notion of
coherent perfect absorption (CPA) as well as extending our analysis to active
resonators (having optical gain). We next provide a physical insight into this
process by using a simple model made of cascaded beam splitters. Importantly,
we confirm our results using a full-wave analysis of realistic material
systems. Finally, we discuss the limitation on the CVA process due to waveform
mismatch and nonlinear effects.
