Ferrite-Enhanced Metamaterials

Patent metadata

Field	Value
Publication number	US-2017093045-A1
Application number	US-201514865600-A
Country	US
Kind code	A1
Filing date	Sep 25, 2015
Priority date	Sep 25, 2015
Publication date	Mar 30, 2017
Grant date	—

Abstract

A method and apparatus for tuning a metamaterial cell. A set of electromagnetic properties of a tunable element associated with the metamaterial cell may be tuned. A resonance of the metamaterial cell may be adjusted in response to the set of electromagnetic properties being tuned. A range of frequencies over which the metamaterial cell provides a negative index of refraction may be changed in response to the resonance of the metamaterial cell changing.

First claim

What is claimed is:

1 . An apparatus comprising:
a metamaterial cell that has a negative index of refraction; and a tunable element associated with the metamaterial cell, wherein tuning a set of electromagnetic properties of the tunable element adjusts a resonance of the metamaterial cell.

2 . The apparatus of claim 1 , wherein the metamaterial cell comprises:
a magnetic resonator; and a conductive structure positioned relative to the magnetic resonator.

3 . The apparatus of claim 2 , wherein the magnetic resonator is a dual split ring resonator.

4 . The apparatus of claim 2 , wherein the tunable element comprises:
a ferromagnetic material associated with at least one side of the conductive structure.

5 . The apparatus of claim 2 , wherein the metamaterial cell further comprises:
a base that is transparent to an electromagnetic field having a natural frequency of the metamaterial cell, wherein the magnetic resonator is disposed on the base.

6 . The apparatus of claim 2 , wherein the conductive structure comprises:
a first conductor; and a second conductor.

7 . The apparatus of claim 6 , wherein the tunable element comprises:
a plurality of liquid crystals located within a reservoir between the first conductor and the second conductor.

8 . The apparatus of claim 1 further comprising:
a tuning device that tunes the set of electromagnetic properties of the tunable element to adjust the resonance of the metamaterial cell.

9 . The apparatus of claim 8 , wherein the tuning device comprises:
a magnetic device that externally applies a magnetic field to the metamaterial cell to tune a magnetic permeability of the tunable element, thereby adjusting the resonance of the metamaterial cell.

10 . The apparatus of claim 8 , wherein the tuning device comprises:
a controllable voltage source that applies an electric field to the tunable element to tune an electric permittivity of the tunable element, thereby adjusting the resonance of the metamaterial cell.

11 . The apparatus of claim 1 , wherein the set of electromagnetic properties includes at least one of an electric permittivity or a magnetic permeability.

12 . The apparatus of claim 1 , wherein the tunable element comprises:
a fluid mixture comprising a plurality of liquid crystals and a plurality of magnetic nanoparticles, wherein tuning at least one of an electric permittivity of the plurality of liquid crystals or a magnetic permeability of the plurality of magnetic nanoparticles adjusts the resonance of the metamaterial cell.

13 . The apparatus of claim 1 , wherein changing the set of electromagnetic properties of the tunable element adjusts the resonance of the metamaterial cell, to thereby adjust a frequency range over which the metamaterial cell yields the negative index of refraction.

14 . The apparatus of claim 1 , wherein the metamaterial cell and the tunable element form a meta-unit that is one of a plurality of meta-units that together form a metamaterial structure.

15 . A metamaterial structure comprising:
a plurality of meta-units, wherein a meta-unit in the plurality of meta-units comprises:
a metamaterial cell; and
a tunable element associated with the metamaterial cell,
wherein tuning at least one of an electric permittivity or a magnetic permeability of the tunable element adjusts a resonance of the metamaterial cell; and
wherein adjusting the resonance for at least a portion of the plurality of meta-units adjusts a frequency range over which the metamaterial structure provides a negative index of refraction for focusing electromagnetic energy.

16 . A method for tuning a metamaterial cell, the method comprising:
tuning a set of electromagnetic properties of a tunable element associated with the metamaterial cell; adjusting a resonance of the metamaterial cell in response to the set of electromagnetic properties being tuned; and changing a range of frequencies over which the metamaterial cell provides a negative index of refraction in response to the resonance of the metamaterial cell changing.

17 . The method of claim 16 , wherein tuning the set of electromagnetic properties comprises:
tuning an electric permittivity of a plurality of liquid crystals located within a reservoir associated with the metamaterial cell to adjust the resonance of the metamaterial cell.

18 . The method of claim 16 , wherein tuning the set of electromagnetic properties comprises:
tuning a magnetic permeability of a plurality of magnetic nanoparticles located within a reservoir associated with the metamaterial cell to adjust the resonance of the metamaterial cell.

19 . The method of claim 16 further comprising:
applying, externally, a magnetic field to the metamaterial cell to adjust the resonance of the metamaterial cell.

20 . The method of claim 16 , wherein tuning the set of electromagnetic properties comprises:
applying an electric field to a fluid mixture located in a reservoir associated with the metamaterial cell, wherein the fluid mixture comprises a plurality of liquid crystals and a plurality of magnetic nanoparticles; changing an alignment of the plurality of liquid crystals in response to the electric field being applied to the fluid mixture; changing an alignment of the plurality of magnetic nanoparticles in response to the alignment of the plurality of liquid crystals changing; and changing a magnetic permeability of the plurality of magnetic nanoparticles in response to the alignment of the plurality of magnetic nanoparticles changing.

Assignees

• Boeing Co

Inventors

• Savage Larry Leon
• Williams John Dalton
• Thacker Corey Mckinney
• Fortinberry Jarrod Douglas
• Bushey Preston Tyler

Classifications

• H01Q1/00

  Details of, or arrangements associated with, antennas (arrangements for varying orientation of directional pattern H01Q3/00) · CPC title

• H01Q15/02

  Refracting or diffracting devices, e.g. lens, prism · CPC title

• H01Q15/0086 Primary

  said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials · CPC title