Complete tunneling of light through impedance-mismatched barrier layers

We investigate the conditions for and properties of the complete tunneling of light through a composite barrier made of impedance-mismatched metamaterial layers. It is shown that two kinds of complete tunneling phenomena exist: phase-unmodulated and phase-modulated complete tunneling. The local surface modes formed near the interfaces between the metamaterial barrier layers play key roles in complete tunneling. Using the terminology of coupled-mode theory, phase-unmodulated complete tunneling occurs through successive mode couplings: from the incident light to the local surface mode and then to the other local surface mode and finally to the light mode in the transmission layer. Phase-modulated complete tunneling results from the complete transfer of the incident optical power to the transmission layer through the direct mediation of the symmetrically and antisymmetrically coupled supermodes of the local surface modes.