Coherent virtual absorption for discretized light.

Coherent virtual absorption (CVA) is a recently introduced phenomenon for which exponentially growing waves incident on a conservative optical medium are neither reflected nor transmitted, at least transiently. CVA has been associated with complex zeros of the scattering matrix and can be regarded as the time reversal of the decay process of a quasi-mode sustained by the optical medium. Here we consider CVA for discretized light transport in coupled resonator optical waveguides or waveguide arrays and show that a distinct kind of CVA, which is not related to the complex zero excitation of quasi-modes, can be observed. This result suggests that a scattering matrix analysis cannot fully capture CVA phenomena.