Resonant transparency of a layered superconductor: Hyperbolic material in the terahertz range tuned by dc magnetic field
N. Kvitka, S. S. Apostolov, N. M. Makarov, T. Rokhmanova, A. A. Shmat’ko, V. A. Yampol’skiı̆
Abstract
We show that layered superconductors, due to their peculiar nonlinear response to a weak dc magnetic field, behave as tunable hyperbolic media within a wide terahertz range. Thereby, various attractive phenomena intrinsic in hyperbolic materials can be controlled by dc magnetic field. In particular, in this work a resonant transparency of a layered superconductor induced by the excitation of localized waves with nonmonotonic dispersion, is studied. We reveal the dc magnetic field is able to adjust the electromagnetic properties of a layered superconductor in order to observe specific twin peaks in the transmittance-vs-angle dependence. In addition, solving the problem by the transfer-matrix method, we succeed in deriving the matrix responsible for the effect of dc magnetic field. It is notable that this specific matrix depends neither on the size of the layered superconductor, nor on the parameters of surroundings.