Low-loss dielectric resonator having a lattice structure with a resonant defect

• US 5,187,461 A
• Filed: 02/15/1991
• Issued: 02/16/1993
• Est. Priority Date: 02/15/1991
• Status: Expired due to Term

• Current Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc), Massachusetts Institute of Technology
• Original Assignee: Lockheed Sanders, Inc. (Martin Marietta Corporation)
• Inventors: Rappe, Andrew, Brommer, Karl, Mullaney, Henry, Meade, Robert, Joanopoulos, John
• Primary Examiner(s): Dzierzynski, Paul M.
• Assistant Examiner(s): Lee, Benny T.
• Application Number:
  US07/656,812
• Time in Patent Office: 732 Days
• Field of Search: 333/219.1, 333/219, 428/304.4, 428/313.3, 428/323
• US Class Current: 333/219.1
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 27/46 Systems using spatial filters
• CPC Class Codes: G02B 5/18 Diffraction gratings holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44
• CPC Class Codes: G02B 5/28 Interference filters
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices
• CPC Class Codes: G02F 2202/32 Photonic crystals
• CPC Class Codes: H01P 1/2005 Electromagnetic photonic bandgaps [EPB], or photonic bandgaps [PBG]
• CPC Class Codes: H01P 1/207 Hollow waveguide filters H01P1/212, H01P1/213, H01P1/215, H01P1/219 take precedence
• CPC Class Codes: H01Q 15/006 Selective devices having photonic band gap materials or materials of which the material properties are frequency dependent, e.g. perforated substrates, high-impedance surfaces
• CPC Class Codes: H01S 5/1042 Optical microcavities, e.g. cavity dimensions comparable to the wavelength
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

A dielectric resonator comprising a resonant defect structure disposed in a lattice structure formed of a plurality of multi-dimensional periodically arranged dielectric elements confines electromagnetic energy within a frequency band in the photonic band gap. The frequency band of the confined electromagnetic energy is tunable. The unique structure of the dielectric resonator leads to reduced power dissipation losses when used in microwave and millimeter wave components. Accordingly, the dielectric resonator

BACKGROUND

This invention was made with government support under Contract Number N00014-86-K-0158 awarded by the Department of the Navy and Contract Number DAAL-03-86-K-0002 awarded by the Department of the Army. The government has certain rights in the invention.

Claims

1. A dielectric resonator comprising:

a first dielectric material for receiving electromagnetic energy;

a lattice structure comprised of a plurality of shaped elements comprised of a second dielectric material and disposed in a multi-dimensional periodic arrangement within the first dielectric material to provide a range of frequencies over a band gap in which the electromagnetic energy within the frequency range of the band gap is prevented from propagating through the lattice structure; and

a resonant defect structure disposed within the lattice structure for introducing a lattice imperfection in the lattice structure, the resonant defect structure providing a frequency range within the band gap in which the electromagnetic energy having frequencies in the frequency range within the band gap is allowed to propagate through the lattice structure.

2. A dielectric resonator as claimed in claim 1 further comprising a coupler connected to the resonant defect structure, the coupler having a first waveguide for coupling the electromagnetic energy into the defect structure and a second waveguide for coupling the electromagnetic energy having frequencies in the frequency range, which is allowed to propagate through the lattice structure, from the resonant defect structure.

3. A dielectric resonator as claimed in claim 1 in which the lattice structure is configured in the form of a face-centered cubic crystal.

4. A dielectric resonator as claimed in claim 1 in which the lattice structure is configured in the form of a diamond lattice crystal.

5. A dielectric resonator as claimed in claim 1 in which the first dielectric material comprises air.

6. A dielectric resonator as claimed in claim 5 in which the shaped elements are spheres, each spherical element having a diameter such that said spherical element overlaps adjacent spherical elements upon being disposed in said multi-dimensional periodic arrangement.

7. A dielectric resonator as claimed in claim 1 in which the shaped elements are spheres.

8. A dielectric resonator as claimed in claim 1 in which the resonant defect structure comprises a dielectric cavity.

9. A dielectric resonator as claimed in claim 1 in which the second dielectric material comprises air.

10. A dielectric resonator comprising:

a first dielectric material for receiving electromagnetic energy;

a lattice structure comprises of a plurality of shaped elements comprising of a second dielectric material and disposed in a multi-dimensional periodic arrangement within the first dielectric material to provide a predetermined frequency band gap in which the electromagnetic energy having frequencies within the band gap is prevented from propagating through the lattice structure;

a resonant defect structure disposed within the lattice structure for providing a lattice imperfection in the lattice structure, the resonant defect structure providing a narrow frequency range within the band gap wherein the electromagnetic energy having frequencies within the narrow frequency range is stored within the resonant defect structure; and

an output coupler linked to the resonant defect structure for coupling the electromagnetic energy having frequencies within the narrow frequency range and being stored in the resonant defect structure therefrom.

11. A dielectric resonator as claimed in claim 10 in which the resonant defect structure comprises a dielectric cavity.

12. A dielectric resonator as claimed in claim 10 further comprising an input coupler for coupling the electromagnetic energy into the defect structure.

13. A dielectric resonator as claimed in claim 10 in which the frequency band gap is within a frequency range of 1-3000 GHz.