Resonator Device for Electron Spin Resonance

• US 20140218032A1
• Filed: 06/28/2013
• Published: 08/07/2014
• Est. Priority Date: 02/01/2013
• Status: Active Grant

• Current Assignee: Quantum Valley Investment Fund LP
• Original Assignee: Quantum Valley Investment Fund LP
• Inventors: Cory, David G., Mohebbi, Hamidreza
• Granted Patent: US 9,841,484 B2
• Time in Patent Office: Days
• US Class Current: 324/316
• CPC Class Codes: G01R 33/34023 Superconducting RF coils
• CPC Class Codes: G01R 33/3415 comprising arrays of sub-coils , i.e. phased-array coils with flexible receiver channels
• CPC Class Codes: G01R 33/3456 Stripline resonators
• CPC Class Codes: G01R 33/60 using electron paramagnetic resonance G01R33/24, G01R33/62 take precedence

Abstract

In some aspects, a resonator device for spin resonance applications is described. In some examples, the resonator device includes a substrate, terminals, and resonators. The terminals include a first terminal having first terminal segments disposed on a substrate surface, and a second terminal having second terminal segments disposed on the substrate surface opposite the first terminal segments. The resonators include conductors disposed on the substrate surface between the first and second terminals. Each conductor is disposed between one of the first terminal segments and a respective, opposite one of the second terminal segments.

Claims

1. An electron spin resonance (ESR) resonator device comprising:

a planar substrate having a substrate surface, and having a ground plane surface opposite the substrate surface;

a ground plane disposed on the ground plane surface;

a first terminal that includes first terminal segments disposed on the substrate surface;

a second terminal that includes second terminal segments disposed on the substrate surface opposite the first terminal segments; and

resonators between the first and second terminals, the resonators including conductors disposed on the substrate surface, each conductor disposed between one of the first terminal segments and a respective, opposite one of the second terminal segments.

2. The ESR resonator device of claim 1, wherein the resonators are microstrip resonators each configured to resonate at the same microwave resonance frequency.

3. The ESR resonator device of claim 1, wherein each of the conductors is elongate and includes:

a first end capacitively coupled to one of the first terminal segments; and

a second, opposite end capacitively coupled to one of the second terminal segments.

4. The ESR resonator device of claim 3, comprising:

a first dielectric volume between the first end of each conductor and one of the first terminal segments; and

a second dielectric volume between the second end of each conductor and one of the second terminal segments.

5. The ESR resonator device of claim 4, wherein the dielectric volume includes at least one of dielectric material or vacuum.

6. The ESR resonator device of claim 1, wherein the conductors are parallel to each other, with equal spacing between each neighboring pair of conductors.

7. The ESR resonator device of claim 1, wherein each of the resonators is a half-wave resonator, a full-wave resonator, or a multi-half-wave resonator.

8. The ESR resonator device of claim 1, wherein each of the resonators is configured to resonate at a resonance frequency, and the length of each resonators is an even number of half-wavelengths for the resonance frequency.

9. The ESR resonator device of claim 1, wherein each of the resonators is configured to resonate at a resonance frequency, and the length of each resonators is an odd number of half-wavelengths for the resonance frequency.

10. The ESR resonator device of claim 1, wherein each of the resonators is configured to provide maximum magnetic field at the center of half-wave segments in the resonator.

11. The ESR resonator device of claim 1, wherein:

the first terminal includes a first terminal conductor disposed on the substrate surface, the first terminal conductor having a first terminal input side and a first terminal segmented side opposite the first terminal input side, the first terminal segmented side including the first terminal segments; and

the second terminal includes a second terminal conductor disposed on the substrate surface, the second terminal conductor having a second terminal input side and a second terminal segmented side opposite the second terminal input side, the second terminal segmented side including the second terminal segments.

12. The ESR resonator device of claim 11, wherein:

the first terminal includes a first branching structure between the first terminal input side and the first terminal segmented side; and

the second terminal includes a second branching structure between the second terminal input side and the second terminal segmented side.

13. The ESR resonator device of claim 12, wherein the first and second branching structures each include one or more tapered branch sections.

14. The ESR resonator device of claim 12, wherein the first and second branching structures each include successive levels between the input side and the respective segmented side, and the individual branches in each level have twice the impedance of the individual branches in the preceding level.

15. The ESR resonator device of claim 11, wherein the first and second terminal conductors and resonator conductors form a surface coil on the substrate.

16. The ESR resonator device of claim 15, comprising a sample region adjacent to the surface coil and opposite the substrate.

17. The ESR resonator device of claim 11, wherein the first and second terminal conductors and the resonator conductors are made of superconducting material.

18. The ESR resonator device of claim 1, wherein the planar substrate includes sapphire.

19. The ESR resonator device of claim 1, wherein the planar substrate includes at least one of silicon or quartz.

20. An electron spin resonance (ESR) method comprising:

receiving an excitation and control signal at a terminal input of an ESR resonator device, the terminal input conductively coupled to terminal output segments;

providing the excitation and control signal from the terminal output segments to a plurality of resonators, the excitation and control signal being delivered in-phase from each of the terminal segments to a respective one of the plurality of resonators; and

producing a magnetic field in a sample region external to the resonators by conducting the excitation and control signal in-phase on the plurality of resonators.

21. The ESR method of claim 20, comprising the plurality of resonators collectively generating a magnetic field that is uniform across a thin sample region.

22. The ESR method of claim 20, comprising:

receiving the excitation and control signal at first and second terminal inputs of the ESR resonator device, the first terminal input conductively coupled to a first set of terminal output segments, the second terminal input conductively coupled to a second set of terminal output segments; and

providing the excitation and control signal to the resonators from the first and second sets of terminal output segments.

23. The ESR method of claim 22, comprising providing the excitation and control signal to the resonators by capacitive coupling between:

the first set of terminal output segments and first ends of the resonators; and

the second set of terminal output segments and second, opposite ends of the resonators.

24. The ESR method of claim 23, comprising producing a microwave frequency magnetic field in the sample region by conducting a microwave frequency signal in-phase on the plurality of resonators.

25. An electron spin resonance (ESR) method comprising:

receiving an excitation and control signal at a planar surface coil disposed on a surface of a substrate, the planar surface coil comprising a plurality of parallel conductors disposed on the surface; and

generating a magnetic field in a sample region adjacent to the surface coil and opposite the substrate, the magnetic field generated by the plurality of parallel conductors each concurrently conducting the excitation and control signal in the same direction and in parallel.

26. The ESR method of claim 25, wherein the parallel conductors are elongate and the method comprises receiving the excitation and control signal at a first plurality of terminal segments at a first end of each conductor and at a second plurality of terminal segments at a second, opposite end of each conductor.

27. The ESR method of claim 26, wherein the parallel conductors are capacitively coupled to the terminal segments.

28. The ESR method of claim 25, comprising manipulating an electron spin in the sample region by the magnetic field.

29. The ESR method of claim 25, wherein the sample region is a planar volume and the magnetic field is uniform across the planar volume.