Enhanced Transmission of Terahertz Radiation through Periodically Modulated Slabs of Layered Superconductors

摘要

We predict the enhanced transmissivity of modulated slabs of layeredsuperconductors for terahertz radiation due to the diffraction of the incidentwave and the resonance excitation of the eigenmodes. The electromagnetic fieldis transferred from the irradiated side of a slab of layered superconductor tothe other one by excited waveguide modes (WGMs) which do not decay deep intothe slab, contrary to metals, where the enhanced light transmission is causedby the excitation of the evanescent surface waves. We show that a series ofresonance peaks (with $T \sim 1$) can be observed in the dependence of thetransmittance $T$ on the varying incidence angle $\theta$, when the dispersioncurve of the diffracted wave crosses successive dispersion curves for the WGMs.