Optically tunable resonant structure

A resonant structure, for supporting electromagnetic (EM) oscillations win a frequency range of approximately 10 GHz to 1000 GHz, and whose resonant properties are controlled by light. The structure includes an interaction material for absorbing light and forming a plasma of electron-hole pairs within the material. Kinetic and potential energy, which are stored in the EM oscillations within the resonant structure, change as a result of the plasma and shift the frequency of the oscillations.

What is claimed and desired to be secured by Letters Patent of the United States is:

1. A resonator, for supporting electromagnetic oscillations within the frequency range of approximately 10 GHz to 1000 GHz, having resonant properties which are controllable by light from a source of light comprising:

a resonant structure having an interaction material having an optical absorption edge not greater than the wavelength of said light, said material being of a type which forms a plasma of electron-hole pairs when illuminated by said source of light, said plasma having sufficient density to change the reactance and dielectric response of said resonant structure thereby shifting the frequency of said electromagnetic oscillations.

2. A resonator as recited in claim 1, wherein said resonant structure is annular.

3. A resonator as recited in claim 2, wherein said resonant structure includes walls of broad and narrow dimensions.

4. A resonator as recited in claim 2, wherein said resonant structure consists essentially of said interaction material.

5. A resonator as recited in claim 3, wherein said broad-dimensioned wall is an external wall and said resonant structure includes a film of said interaction material attached to an external broad-dimensioned wall of said resonant structure.

6. A resonator as recited in claim 3, wherein said resonant structure is metal and said interaction material is confined between the broad- and narrow-dimensioned walls, a wall of said resonant structure having an opening through which light may pass for illuminating said interaction material.

7. A resonant structure as recited in claim 4, wherein said interaction material comprises semiconductor material.

8. A resonant structure as recited in claim 7, wherein said semiconductor material is of resistivity approximately equal to or greater than ten ohm-centimeters.

9. A resonant structure as recited in claim 7, wherein said light penetrates approximately ten percent or less of said semiconductor material.

10. A resonant structure as recited in claim 8, wherein said semiconductor material is selected from the group consisting of covalently bonded semiconductors.

11. A resonant structure as recited in claim 10, wherein said covalently bonded semiconductors are selected from the group consisting of silicon and germanium.

12. A resonant structure as recited in claim 5, wherein said resonant structure is formed from a dielectric material and said film of interaction material is formed from semiconductor material, the permittivity of the dielectric being approximately equal to the permittivity of the semiconductor.

13. A resonant structure as recited in claim 12, wherein said semiconductor material is of resistivity approximately equal to or greater than ten ohm-centimeters.

14. A resonant structure as recited in claim 12, wherein the thickness of said film of semiconductor material is approximately ten percent or less of the thickness of the narrow-dimensioned wall of said dielectric resonant structure, and said light penetrates the entire thickness of the film of semiconductor material.

15. A resonant structure as recited in claim 13, wherein said semiconductor material is selected from the group consisting of covalently bonded semiconductors.

16. A resonant structure as recited in claim 15, wherein said covalently bonded semiconductors are selected from the group consisting of silicon and germanium.

17. A resonant structure as recited in claim 6, wherein said interaction material is attached to an internal narrow-dimensioned wall of said resonant structure, a narrow-dimensioned wall of said resonant structure being opposite the wall to which said interaction material is attached and having an opening through which light may pass for illuminating said interaction material.

18. A resonant structure as recited in claim 17, wherein said internal narrow-dimensioned wall is the internal wall of large circumference.

19. A resonant structure as recited in claim 6, wherein said interaction material is formed from semiconductor material.

20. A resonant structure as recited in claim 19, wherein said semiconductor material is of resistivity approximately equal to or greater than ten ohm-centimeters.

21. A resonant structure as recited in claim 19, wherein the thickness of said semiconductor material is approximately ten percent or less of the broad-dimensioned wall of said resonant structure and said light penetrates the entire thickness of the semiconductor material.

22. A resonant structure as recited in claim 20, wherein said semiconductor material is selected from the group consisting of covalently bonded semiconductors.

23. A resonant structure as recited in claim 22, wherein said covalently bonded semiconductors are selected from the group consisting of silicon and germanium.