NANOSCALE SCANNING SENSORS

• US 20150253355A1
• Filed: 08/20/2013
• Published: 09/10/2015
• Est. Priority Date: 08/22/2012
• Status: Active Grant

• Current Assignee: President and Fellows of Harvard College (Harvard Corporation)
• Original Assignee: President and Fellows of Harvard College (Harvard Corporation)
• Inventors: Grinolds, Michael S., Hong, Sungkun, Maletinsky, Patrick, Yacoby, Amir
• Granted Patent: US 10,041,971 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 2201/10 Scanning
• CPC Class Codes: G01N 24/10 by using electron paramagnetic resonance G01N24/12 takes precedence
• CPC Class Codes: G01Q 30/025 Optical microscopes coupled with SPM
• CPC Class Codes: G01Q 60/08 MFM [Magnetic Force Microscopy] combined with AFM [Atomic Force Microscopy
• CPC Class Codes: G01Q 60/38 Probes, their manufacture, or their related instrumentation, e.g. holders
• CPC Class Codes: G01Q 60/52 Resonance
• CPC Class Codes: G01Q 60/54 Probes, their manufacture, or their related instrumentation, e.g. holders
• CPC Class Codes: G01Q 70/14 Particular materials
• CPC Class Codes: G01R 33/022 Measuring gradient
• CPC Class Codes: G01R 33/032 using magneto-optic devices, e.g. Faraday or Cotton-Mouton effect
• CPC Class Codes: G01R 33/1284 Spin resolved measurements; Influencing spins during measurements, e.g. in spintronics devices G01R33/093 takes precedence; semiconductor devices using spin polarized carriers H01L29/66984
• CPC Class Codes: G01R 33/323 Detection of MR without the use of RF or microwaves, e.g. force-detected MR, thermally detected MR, MR detection via electrical conductivity, optically detected MR
• CPC Class Codes: G01R 33/60 using electron paramagnetic resonance G01R33/24, G01R33/62 take precedence

Abstract

A sensing probe may be formed of a diamond material comprising one or more spin defects that are configured to emit fluorescent light and are located no more than 50 nm from a sensing surface of the sensing probe. The sensing probe may include an optical outcoupling structure formed by the diamond material and configured to optically guide the fluorescent light toward an output end of the optical outcoupling structure. An optical detector may detect the fluorescent light that is emitted from the spin defects and that exits through the output end of the optical outcoupling structure after being optically guided therethrough. A mounting system may hold the sensing probe and control a distance between the sensing surface of the sensing probe and a surface of a sample while permitting relative motion between the sensing surface and the sample surface.

Claims

1. A sensing probe formed of a diamond material, the sensing probe comprising:

one or more spin defects configured to emit fluorescent light; and

an optical outcoupling structure formed by the diamond material, the optical outcoupling structure configured to optically guide the fluorescent light emitted by the one or more spin defects toward an output end of the optical outcoupling structure,

wherein the one or more spin defects are located no more than 50 nm from a sensing surface of the sensing probe,

wherein the sensing probe including the optical outcoupling structure is formed of a diamond component having at least one linear dimension greater than 1 μ

m in length.

2. The sensing probe of claim 1, wherein the one or more spin defects are located no more than 40 nm, 30 nm, 20 nm, 15 nm, 12 nm, or 10 nm from the sensing surface of the sensing probe.

3. The sensing probe of claim 1, wherein the one or more spin defects are NV⁻

(nitrogen-vacancy) defects.

4. The sensing probe of claim 1, wherein a decoherence time of the one or more spin defects is greater than 10 μ

sec, 50 μ

sec, 100 μ

sec, 200 μ

sec, 300 μ

sec, 500 μ

sec, or 700 μ

sec.

5. The sensing probe of claim 1, wherein the sensing probe including the optical outcoupling structure is formed of a single crystal diamond material.

6. The sensing probe of claim 1, wherein the optical outcoupling structure is formed by one of:

a nanopillar;

a solid immersion lens;

or via internal reflection.

7. The sensing probe of claim 6, wherein the optical outcoupling structure is formed of a nanopillar.

8. The sensing probe of claim 7, wherein the nanopillar has a diameter between 100 nm and 300 nm, and a length between 0.5 μ

m and 5 μ

m.

9. The sensing probe of claim 1, wherein the sensing robe comprises no more than 50, 30, 10, 5, 3, 2, or 1 s in defects located no more than 50 nm from the sensing surface and optically coupled to the optical outcoupling structure.

10. The sensing probe of claim 1, wherein the sensing probe comprises more than 50 spin defects in the form of a layer located no more than 50 nm from the sensing surface and optically coupled to the optical outcoupling structure.

11. A system comprising:

a sensing probe formed of a diamond material, the sensing probe comprising one or more spin defects configured to emit fluorescent light, and an optical outcoupling structure formed by the diamond material, the optical outcoupling structure configured to optically guide the fluorescent light emitted by the one or more spin defects toward an output end of the optical outcoupling structure,

wherein the one or more spin defects are located no more than 50 nm from a sensing surface of the sensing probe, and wherein the sensing probe including the optical outcoupling structure is formed of a diamond component having at least one linear dimension greater than 1 μ

m in length;

an optical excitation source configured to generate excitation light directed to the one or more spin defects causing the one or more spin defects to fluoresce;

an optical detector configured to detect the fluorescent light that is emitted from the one or more spin defects and that exits through the output end of the optical outcoupling structure after being optically guided therethrough; and

a mounting system configured to hold the sensing probe and control a distance between the sensing surface of the sensing probe and a surface of a sample while permitting relative motion between the sensing surface of the sensing probe and the sample surface.

12. The system of claim 11, wherein the mounting system comprises an AFM (atomic force microscope).

13. The system of claim 11, comprising an optical microscope coupled to the mounting system and configured to optically address and readout the one or more spin defects.

14. The system of claim 11, further comprising a microwave source, and wherein the microwave source is configured to generate microwaves tuned to a resonant frequency of at least one of the spin defects.

15. The system of claim 14, wherein the one or more spin defects are NV defects, and wherein the system is configured to detect an external magnetic field by measuring a Zeeman shift of a spin state of the NV defects.

16. The system of claim 15, wherein the microwaves comprise a spin-decoupling sequence of pulses, and wherein the sequence includes at least one of:

a Hahn spin-echo pulse sequence;

a CPMG (Carr Purcell Meiboom Gill) pulse sequence;

an XY pulse sequence; and

a MREVB pulse sequence.

17. The system of claim 11, wherein the system is configured to have an AC magnetic field detection sensitivity better than 200, 100, 75, 60, 50, 25, 10, or 5 nT Hz⁻

1/2.

18. The system of claim 11, wherein the system is configured to have a DC magnetic field detection sensitivity better than 50, 20, 10, 6, 4, 1, or 0.5 μ

T Hz<sup>−

1/2</sup>.

19. The system of claim 11, wherein the system is configured to resolve single spin defects in a sample.

20. The system of claim 19, wherein required integration time for single spin imaging with a signal to noise ratio of 2 is less than 5 mins, 3 mins, 2 mins, 1 min, 30 seconds, 15 seconds, 10 seconds, 5 seconds, 2 seconds, 1 second, or 0.5 second.

21-46. -46. (canceled)