TUNABLE SUPERCONDUCTING RESONATOR AND METHODS OF TUNING THEREOF

• US 20040021466A1
• Filed: 03/19/2003
• Published: 02/05/2004
• Est. Priority Date: 08/25/1992
• Status: Active Grant

• Current Assignee: Superconductor Technologies Inc. (Clearday, Inc.)
• Original Assignee: Superconductor Technologies Inc. (Clearday, Inc.)
• Inventors: James, Timothy W., Sun, Jonathan Z., Bourne, Lincoln C., Hammond, Robert B., Scalapino, Douglas J.
• Granted Patent: US 6,727,702 B2
• Time in Patent Office: Days
• US Class Current: 324/318
• CPC Class Codes: G01R 33/34007 Manufacture of RF coils, e.g. using printed circuit board technology; additional hardware for providing mechanical support to the RF coil assembly or to part thereof, e.g. a support for moving the coil assembly relative to the remainder of the MR system
• CPC Class Codes: G01R 33/34023 Superconducting RF coils
• CPC Class Codes: G01R 33/34053 Solenoid coils; Toroidal coils
• CPC Class Codes: G01R 33/341 comprising surface coils
• CPC Class Codes: G01R 33/3642 Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification
• CPC Class Codes: G01R 33/3671 involving modulation of the quality factor of the RF coil G01R33/3642 takes precedence
• CPC Class Codes: H01F 6/06 Coils, e.g. winding, insulating, terminating or casing arrangements therefor
• CPC Class Codes: H01G 4/008 Selection of materials
• CPC Class Codes: H01P 1/203 Strip line filters
• CPC Class Codes: H01P 7/08 Strip line resonators
• CPC Class Codes: H01P 7/088 Tunable resonators
• CPC Class Codes: H01Q 1/364 using a particular conducting material, e.g. superconductor
• CPC Class Codes: H03K 17/78 using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled
• CPC Class Codes: H03K 17/92 by the use, as active elements, of superconductive devices
• CPC Class Codes: H03K 2217/0036 Means reducing energy consumption

Abstract

A method of tuning a high temperature superconductor (HTS) resonator includes the steps of providing a HTS inductor and a HTS capacitor, the HTS capacitor being electrically connected to the HTS inductor. A tuning body is provided adjacent to the HTS inductor and the HTS capacitor. The relative position of the tuning body with respect to the HTS inductor and the HTS capacitor is altered so as to tune the resonator. A tunable resonant circuit is provided that includes a substrate having a planar surface. At least one resonator formed from HTS material is disposed on the substrate, the resonator having one or more turns that when combined, turn through greater than 360°.

Claims

1. A method of tuning a high temperature superconducting resonator comprising the steps of:

providing a high temperature superconducting inductor;

providing a high temperature superconducting capacitor, the capacitor being electrically connected to the high temperature superconducting inductor;

providing a tuning body adjacent to the high temperature superconducting inductor and the high temperature superconducting capacitor; and

altering the relative position of the tuning body with respect to the high temperature superconducting inductor and the high temperature superconducting capacitor so as to tune the resonator.

2. The method according to claim 1, wherein the tuning body is a dielectric.

3. The method according to claim 1, wherein the tuning body is a conductor.

4. The method according to claim 1, wherein the tuning body is a superconductor.

5. The method according to claim 1, wherein the step of altering the relative position of the tuning body with respect to the high temperature superconducting inductor and the high temperature superconducting capacitor produces dynamic tuning of the resonator.

6. The method according to claim 1, wherein the high temperature superconducting inductor and the high temperature superconducting capacitor comprise an epitaxial thin film superconductor.

7. The method according to claim 1, wherein the high temperature superconducting inductor is formed on a dielectric substrate.

8. The method according to claim 7, wherein the dielectric substrate is a wafer having a diameter of two inches or less.

9. The method according to claim 1, wherein the high temperature superconducting inductor has at least fifteen coils.

10. The method according to claim 1, wherein the high temperature superconducting inductor comprises a coil with a line width of about 200μ

.

11. The method according to claim 1, wherein the high temperature superconducting inductor comprises a coil with a pitch of approximately 400μ

.

12. A method of tuning magnetically coupled high temperature superconducting resonators comprising the steps of:

providing a first high temperature superconducting resonator;

providing a second high temperature superconducting resonator in proximity to the first high temperature superconducting resonator so as to couple the first high temperature superconducting resonator to the second high temperature superconducting resonator; and

tuning one of the first and second high temperature superconducting resonators.

13. The method according to claim 12, wherein the high temperature superconducting resonators are formed using a thallium-based superconductor.

14. The method according to claim 12, wherein the high temperature superconducting resonators are formed using a yttrium-based material.

15. The method according to claim 12, wherein the high temperature superconducting resonators are formed using a bismuth-based material.

16. The method according to claim 12, wherein the step of tuning is performed by scribing one of the first and second high temperature superconducting resonators.

17. The method according to claim 12, wherein the step of tuning is performed by providing a tuning body adjacent to the first and second high temperature superconducting resonators and altering the relative position of tuning body with respect to the first and second high temperature superconducting resonators.

18. The method according to claim 12, wherein the high temperature superconducting resonators are formed with an epitaxial thin film superconductor.

19. The method according to claim 17, wherein the tuning body is a dielectric.

20. The method according to claim 17, wherein the tuning body is a conductor.

21. The method according to claim 17, wherein the tuning body is a superconductor.

22. A tunable resonant circuit comprising:

a substrate having a planar surface;

at least one resonator formed from a high temperature superconducting material formed on the substrate, the resonator having one or more turns, when combined, turn through greater than 360°

.

23. The tunable resonant circuit of claim 22, wherein the at least one high temperature superconducting resonator is formed using a thallium-based superconductor.

24. The tunable resonant circuit of claim 22, wherein the at least one high temperature superconducting resonator is formed using a yttrium-based material.

25. The tunable resonant circuit of claim 22, wherein the at least one high temperature superconducting resonator is formed using a bismuth-based material.

26. The tunable resonant circuit of claim 22, wherein the at least one high temperature superconducting resonator is formed with an epitaxial thin film superconductor.

27. The method according to claim 22, wherein the substrate comprises a dielectric material.

28. The method according to claim 27, wherein the substrate is a wafer having a diameter of two inches or less.

29. The method according to claim 22, wherein the high temperature superconducting inductor has at least fifteen coils.

30. The method according to claim 22, wherein the high temperature superconducting inductor comprises a coil with a line width of about 200μ

.

31. The method according to claim 22, wherein the high temperature superconducting inductor comprises a coil with a pitch of approximately 400μ

.