Yamaguchi University

University of California

Semiconductor Technology Academic Research Center

Atsushi Sanada

Tatsuo Itoh

Christophe Caloz

A metamaterial including at least one spiral conductor. Only a magnetic permeability selected from among an effective dielectric constant and the magnetic permeability of the metamaterial becomes negative, so that the metamaterial have a negative refractive index characteristic. The material includes a plurality of unit cells arrayed in one of one-dimensional direction, two-dimensional directions, and three-dimensional directions. Each of the unit cells includes a dielectric substrate having first and second surfaces disposed in a substantially parallel relationship, and first and second spiral conductors. The first spiral conductor is formed on the first surface of the dielectric substrate, and the second spiral conductor is formed in one of a same direction as and an opposite direction to the first spiral conductor, on the second surface of the dielectric substrate, to oppose the first spiral conductor and to be electromagnetically coupled with the first spiral conductor.

Metamaterial provided with at least one spiral conductor for propagating electromagnetic wave

A two-dimensional left-handed metamaterial that functions as a two-dimensional electromagnetic wave propagation medium in which the equivalent permittivity and permeability of the medium are both negative, exhibits superior low-loss, broadband characteristics as a left-handed material, and has a simple constitution, enabling low-cost manufacture.

Two-dimensional left-handed metamaterial

A three-dimensional left-handed metamaterial having a completely new constitution, which functions as a three-dimensional electromagnetic wave propagation medium and in which an equivalent permittivity and a permeability of the medium simultaneously take negative values. The three-dimensional left-handed metamaterial is structured such that cubic unit cellsare disposed repeatedly in three orthogonal directions of a three-dimensional space, and includes: a first particleconstituted by a conductor and disposed in positions centering on respective vertices of the unit cell; a second particleconstituted by a conductor and disposed in positions centering on face center points, which are centers of respective faces of the unit cell; a first connecting portion constituted by a conductor, which connects the first particles to a center point of the unit cell; and a second connecting portion constituted by a conductor, which connects the second particles to the center point.

Three-dimensional left-handed metamaterial

The present invention provides a sripline-type transmission line which can easily change and control transmission characteristics by changing the permittivity of a substrate, and also provides an antenna that can extensively change and control the direction of radiation with the frequency of an electromagnetic wave constant, by using this transmission line.

Stripline-type composite right/left-handed transmission line or left-handed transmission line, and antenna that uses same

Each of unit cells constituting a negative permeability medium includes a metal patch formed on a surface of a dielectric substrate. The dielectric substrate has a rear surface having a ground conductor formed on its entire surface. A positive permeability medium is an existing micro strip line and each of unit cells has a two-dimensional structure having a metal strip connected in four directions. The dielectric substrate has a rear surface having a ground conductor formed on its entire surface. The negative permeability medium is arranged at the left side adjacent to the positive permeability medium formed by unit cells arranged at the right side so that the media oppose to each other. A waveguide formed by the positive/negative permittivity medium or the positive/negative permeability medium of the meta material for propagation of a surface wave is formed at the boundary of the two media.

Negative permeability or negative permittivity meta material and surface wave waveguide

A two-dimensional structure medium comprising a conductor pattern as unit cells formed on the upper surface of a substrate and a conductor pattern formed on the lower surface of the substrate and exhibiting a left-handed characteristic achieved without using a via by utilizing the interaction between an inductance component formed by connecting a part of a floating island pattern out of the conductor pattern on the lower surface of the substrate with a pattern as the ground portion and a capacitance component of parallel-plate mode formed by the conductor pattern on the upper surface of the substrate and the conductor pattern on the lower surface of the substrate.

Left-handed medium using no via

A high frequency resonator circuit and method of fabrication is described which has a resonant frequency independent of physical resonator dimensions. The resonator operates in a zeroeth-order mode on a composite right/left-handed (CRLH) transmission line (TL). The LH wave properties of the CRLH-TL contributing anti-parallel phase and group velocities. In one variation, the unit cells are formed from microstrip techniques, preferably creating alternating interdigitated capacitors and stub inductors. The resonant wavelength of the resonator is dependent on the electrical characteristics of the unit cells and not the physical size of the resonator in relation to the desired resonant wavelength. The resonator is created with at least 1.5 unit cells and the Q of the resonator is substantially independent of the number of unit cells utilized. The resonator circuit is particularly well suited for reducing resonator size, and allows resonators of various wavelengths to be fabricated within a fixed board area.

Growing community of inventors

Yamaguchi, Japan

Atsushi Sanada