Yasuhiro Tamayama

Storage of electromagnetic waves in a metamaterial that mimics electromagnetically induced transparency

We propose a method for dynamically controlling the properties of a metamaterial that mimics electromagnetically induced transparency (EIT) by introducing varactor diodes to manipulate the structural symmetry of the metamaterial. Dynamic modulation of the EIT property enables the storage and retrieval of electromagnetic waves. We confirmed that the electromagnetic waves were stored and released, while maintaining the phase distribution in the propagating direction.

Variable group delay in a metamaterial with field-gradient-induced transparency

We realize variable control of the group delay in an electromagnetically induced transparency-like metamaterial. Its unit cell is designed to have a bright mode and a dark mode. The coupling strength between these two modes is determined by the electromagnetic field gradient. In this metamaterial with field-gradient-induced transparency, the group delay at the transparency frequency can be varied by varying the incident angle of the electromagnetic plane waves. By tilting a single layer of the metamaterial, the group delay of a microwave pulse can be varied between 0.50 and 1.85 ns.

Observation of Brewster's effect for transverse-electric electromagnetic waves in metamaterials: Experiment and theory

We have experimentally realized Brewsters effect for transverse-electric waves with metamaterials. In dielectric media, Brewsters no-reflection effect arises only for transverse-magnetic waves. However, it has been theoretically predicted that Brewsters effect arises for TE waves under the condition that the relative permeability

Electromagnetically induced transparency like transmission in a metamaterial composed of cut-wire pairs with indirect coupling

{\ensuremath{\mu}}_{\mathrm{r}}

Efficient second harmonic generation in a metamaterial with two resonant modes coupled through two varactor diodes

is not equal to unity. We have designed an array of split-ring resonators as a metamaterial with

A linear-to-circular polarization converter with half transmission and half reflection using a single-layered metamaterial

{\ensuremath{\mu}}_{\mathrm{r}}\ensuremath{\ne}1

An invisible medium for circularly polarized electromagnetic waves

using a finite-difference time-domain method. The reflection measurements were carried out in a

Enhancement of second harmonic generation in a doubly resonant metamaterial

3\text{\ensuremath{-}}\mathrm{GHz}

Plasma metamaterials as cloaking and nonlinear media

region and the disappearance of reflected waves at a particular incident angle was confirmed.

Electromagnetic response of a metamaterial with field-gradient-induced transparency

(Received 21 October 2013; revised manuscript received 22 January 2014; published 18 February 2014)We theoretically and numerically investigate metamaterials composed of coupled resonators with indirectcoupling. First, we theoretically analyze a mechanical model of coupled resonators with indirect coupling.The theoretical analysis shows that an electromagnetically induced transparency (EIT)-like phenomenon with atransparency bandwidth narrower than the resonance linewidths of the constitutive resonators can occur in themetamaterial with strong indirect coupling. We then numerically examine the characteristics of the metamaterialcomposedofcoupledcut-wirepairsusingafinite-differencetime-domain(FDTD)method.TheFDTDsimulationconfirmsthatanEIT-liketransparencyphenomenonoccursinthemetamaterialowingtoindirectcoupling.Finally,we compare the results of the theoretical and numerical analyses. The behavior of the EIT-like metamaterial isfound to be well described by the mechanical model of the coupled resonators.DOI: 10.1103/PhysRevB.89.075120 PACS number(s): 78