Diamond nanowires

• US 8,415,640 B2
• Filed: 04/19/2011
• Issued: 04/09/2013
• Est. Priority Date: 04/19/2010
• Status: Active Grant

• Current Assignee: President and Fellows of Harvard College (Harvard Corporation), Texas A&M University System
• Original Assignee: President and Fellows of Harvard College (Harvard Corporation)
• Inventors: Babinec, Thomas M., Khan, Mughees, Zhang, Yinan, Hemmer, Philip R., Loncar, Marko, Hausmann, Birgit J. M.
• Primary Examiner(s): Kim, Kiho
• Application Number:
  US13/089,547
• Publication Number:
  US 20110309265A1
• Time in Patent Office: 721 Days
• Field of Search: 250/459.1
• US Class Current: 250/458.1
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G01N 21/64 Fluorescence; Phosphorescence

Abstract

In a general aspect, a system includes a plurality of diamond nanowires disposed on the surface of a diamond substrate, at least some of the nanowires including a color center. The system also includes a light source configured to illuminate at least one of the plurality of nanowires with excitation light at a wavelength corresponding to an excitation wavelength of the color center included in the illuminated nanowire; and an optical receiver configured to receive a fluorescence emitted from the color center included in the illuminated nanowire in response to the excitation light.

Claims

1. A system comprising:

a plurality of diamond nanowires disposed on the surface of a diamond substrate that includes a plurality of color centers, at least some of the nanowires formed in the substrate with portions of the surface of the substrate selectively removed in a region including at least one color center to include a color center in at least some of the nanowires;

a light source configured to illuminate at least one of the plurality of nanowires with excitation light at a wavelength corresponding to an excitation wavelength of the color center included in the illuminated nanowire; and

an optical receiver configured to receive a fluorescence emitted from the color center included in the illuminated nanowire in response to the excitation light.

2. The system of claim 1, wherein the optical receiver is at least one of an optical fiber and a detector.

3. The system of claim 1, wherein each nanowire has a diameter of about 200 nm and a length of about 2 μ

m.

4. The system of claim 3, wherein the length of the nanowires is in a direction perpendicular to the surface of the substrate.

5. The system of claim 1, wherein a lifetime of the fluorescence emitted from the at least one color center is between about 10 ns and about 25 ns.

6. The system of claim 1, wherein a first end of the illuminated nanowire is in contact with the surface of the substrate, and wherein the optical receiver is positioned to receive the emitted fluorescence from a distal end of the illuminated nanowire.

7. The system of claim 1, wherein the fluorescence is emitted from the at least one color center in a mode propagating substantially perpendicularly away from the surface of the substrate.

8. The system of claim 1, wherein the optical receiver is positioned to receive at least 10% of the emitted fluorescence.

9. The system of claim 1, wherein the fluorescence includes at least 100,000 photons per second.

10. The system of claim 1, wherein the illuminated nanowire is configured to emit fluorescence at a temperature greater than about 300 K.

11. A method comprising:

providing a diamond substrate that includes a plurality of color centers; and

selectively removing a portion of the surface of the substrate to provide a plurality of diamond nanowires, including selectively removing a portion of the surface of the substrate in a region including at least one color center.

12. The method of claim 11, wherein the plurality of color centers in the diamond substrate are distributed substantially randomly.

13. The method of claim 11, further comprising implanting at least one color center in at least some of the plurality of diamond nanowires.

14. The method of claim 11, further comprising forming a microelectromechanical systems (MEMS) or nanoelectromechanical systems (NEMS) device including at least one of the plurality of diamond nanowires.

15. The method of claim 14, wherein the MEMS or NEMS device includes at least one of a mechanical resonator and an atomic force microscopy (AFM) probe.

16. The method of claim 11, further comprising:

illuminating at least some of the plurality of nanowires with excitation light at a wavelength corresponding to an excitation wavelength of the nitrogen vacancy centers; and

receiving a fluorescence emitted from at least one nitrogen vacancy center in response to the excitation.

17. The method of claim 16 wherein receiving the fluorescence includes detecting at least 10% of the emitted fluorescence.

18. The method of claim 16, wherein receiving the fluorescence includes receiving the fluorescence into an optical fiber.

19. The method of claim 11, wherein selectively removing a portion of the surface of the substrate includes fabricating nanowires with diameter of about 200 nm and a length of about 2 μ

m.

20. The method of claim 11, wherein selectively removing a portion of the surface of the substrate includes:

lithographically defining a pattern on the surface of the substrate corresponding to an arrangement of the nanowires; and

etching the surface of the substrate according to the lithographically defined pattern.

21. The method of claim 20, wherein etching the surface of the substrate includes performing a reactive ion etch for about 10 minutes.

22. The method of claim 21, wherein performing the reactive ion etch includes:

applying an inductively coupled plasma (ICP) power of about 700 W for about two minutes;

applying an ICP power of about 600 W for about three minutes; and

applying an ICP power of about 1000 W for about five minutes.

23. The method of claim 21, wherein performing the reactive ion etch includes performing the etch under at least one of the following conditions:

in an atmosphere of 30 sccm of oxygen gas, at a pressure of 10 mTorr, and at a bias power of about 100 W.