Graphene sheet and nanomechanical resonator

Patent metadata

Field	Value
Publication number	US-9973111-B2
Application number	US-201615137971-A
Country	US
Kind code	B2
Filing date	Apr 25, 2016
Priority date	Feb 16, 2012
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A nanomechanical resonator includes processing electronics configured to control an actuator to actively control a resonant frequency of a portion of a graphene sheet by applying a variable out-of-plane force to the graphene sheet. The graphene sheet is at least partially suspended from a support structure and has a carbon lattice that substantially defines a plane.

First claim

What is claimed is:

1. A nanomechanical resonator, comprising:
processing electronics configured to control an actuator to actively control a resonant frequency of a portion of a graphene sheet by applying a variable out-of-plane force to the graphene sheet, the graphene sheet at least partially suspended from a support structure and having a carbon lattice that substantially defines a plane.

2. The resonator of claim 1 , wherein the graphene sheet includes a length dimension and a width dimension, and wherein the length dimension is comparable with the width dimension.

3. The resonator of claim 2 , wherein the graphene sheet forms a drum head.

4. The resonator of claim 2 , wherein the graphene sheet substantially forms at least one of a circle, a rectangle, and a polygon.

5. The resonator of claim 2 , wherein the graphene sheet is fully supported around a perimeter of the graphene sheet.

6. The resonator of claim 2 , wherein the graphene sheet comprises a free surface disposed along a perimeter of the graphene sheet.

7. The resonator of claim 2 , wherein the graphene sheet comprises an interior surface, and wherein the interior surface is a free surface.

8. The resonator of claim 2 , wherein the graphene sheet comprises an interior surface, and wherein the support structure couples to the interior surface of the graphene sheet.

9. The resonator of claim 1 , wherein the actuator is configured to mechanically vary the out-of-plane force, and wherein the actuator comprises a piezoelectric actuator coupled to a support structure.

10. The resonator of claim 1 , wherein the actuator is configured to change the resonant frequency of the graphene sheet to a new value.

11. The resonator of claim 1 , wherein the actuator is configured to control the resonant frequency of the graphene sheet to a reference value in response to an environmental disturbance.

12. A method of controlling a resonant frequency of a graphene nanomechanical resonator, comprising:
controlling, by processing electronics, an actuator to actively control a resonant frequency of a portion of a graphene sheet by applying an out-of-plane force to the graphene sheet, the graphene sheet at least partially suspended from a support structure and having a carbon lattice that substantially defines a plane.

13. The method of claim 12 , wherein the graphene sheet includes a length dimension and a width dimension, and wherein the length dimension is at least three times greater than the width dimension.

14. The method of claim 12 , wherein the graphene sheet includes a length dimension and a width dimension, and wherein the length dimension is at least ten times greater than the width dimension.

15. The method of claim 14 , wherein the graphene sheet includes a first end and a second end disposed lengthwise opposite the first end, and wherein the graphene sheet is supported at the first end by the support structure.

16. The method of claim 15 , further comprising a second support structure;
wherein the second end of the graphene sheet is supported by the second support structure.

17. The method of claim 16 , further comprising suspending the second end of the graphene sheet from the second support structure.

18. The method of claim 12 , wherein the graphene sheet is supported by a plurality of supports and is subject to an in-plane stress field.

19. The method of claim 18 , wherein the in-plane stress field is purely tensile.

20. The method of claim 18 , wherein the in-plane stress field includes a shear component.

21. The method of claim 18 , wherein the in-plane stress field is isotropic.

22. The method of claim 18 , wherein the in-plane stress field is anisotropic.

23. The method of claim 18 , wherein the out-of-plane force applied to the graphene sheet is configured to interact with the in-plane stress field to modify at least one of the modes and resonant frequency of the resonator.

24. The method of claim 18 , further comprising applying the out-of-plane force to the graphene sheet such that the out-of-plane force interacts with the in-plane stress field to modify at least one of the modes and resonant frequency of the resonator.

25. A method of controlling a resonant frequency of a graphene nanomechanical resonator, comprising:
controlling, by processing electronics, a resonant frequency of a portion of a graphene sheet by applying an out-of-plane force to the graphene sheet, the graphene sheet at least partially suspended from a support structure and having a carbon lattice that substantially defines a plane.

26. The method of claim 25 , wherein varying the out-of-plane force comprises varying a support boundary condition.

27. The method of claim 26 , wherein varying the support boundary condition modifies the resonant frequency of the resonator.

28. The method of claim 26 , wherein varying the out-of-plane force increases coupling between the graphene sheet and at least one support structure.

29. The method of claim 26 , wherein varying the out-of-plane force decreases coupling between the graphene sheet and at least one support structure.

30. The method of claim 26 , wherein varying the out-of-plane force increases an unsupported length of the graphene sheet.

31. The method of claim 26 , wherein varying the out-of-plane force decreases an unsupported length of the graphene sheet.

32. The method of claim 26 , wherein varying the out-of-plane force uniformly varies the out-of-plane force over a width of the graphene sheet.

33. The method of claim 26 , wherein varying the out-of-plane force uniformly varies the out-of-plane force over a perimeter of the graphene sheet.

34. The method of claim 26 , wherein the out-of-plane force is limited to a specified region of the graphene sheet.

35. The method of claim 26 , wherein the out-of-plane force is limited to a plurality of specified regions of the graphene sheet.

Assignees

• Elwha Llc

Inventors

• Duncan William D
• Hyde Roderick A
• Kare Jordin T
• Weaver Thomas A
• Wood Jr Lowell L

Classifications

• C01B32/194

  After-treatment · CPC title

• Y10S977/734

  Fullerenes, i.e. graphene-based structures, such as nanohorns, nanococoons, nanoscrolls or fullerene-like structures, e.g. WS2 or MoS2 chalcogenide nanotubes, planar C3N4, etc. · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• C01B32/182 Primary

  Graphene · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title