MICRO-DNV DEVICE

• US 20160146904A1
• Filed: 09/25/2015
• Published: 05/26/2016
• Est. Priority Date: 09/25/2014
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: HILTABIDLE, Michael J., KAUP, Peter G., MANICKAM, Arul, STETSON, John B. Jr., SIMON, Sarah
• Granted Patent: US 10,168,393 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 33/0052 Manufacturing aspects; Manufacturing of single devices, i.e. of semiconductor magnetic sensor chips devices based on galvano-magnetic effect or the like H10N50/85
• CPC Class Codes: G01R 33/032 using magneto-optic devices, e.g. Faraday or Cotton-Mouton effect
• 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 33/64 using cyclotron resonance G01R33/24 takes precedence
• CPC Class Codes: G01R 35/005 Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references G01R33/0035, G01R35/002 take precedence

Abstract

A method for providing a miniature vector magnetometer includes embedding a micron-sized diamond nitrogen-vacancy (DNV) crystal into a bonding material. The bonding material including the embedded micron-sized DNV crystal is cured to form a micro-DNV sensor. A micro-DNV assembly is formed by integrating the micro-DNV sensor with a micro-radio-frequency (RF) source, a micron-sized light source, a reference bias magnet, and one or more micro-photo detectors. The micro-DNV assembly is operable to perform vector magnetometry when positioned in an external magnetic field.

Claims

1. A method for providing a vector magnetometer, the method comprising:

embedding a micron-sized diamond nitrogen-vacancy (DNV) crystal into a bonding material to form a micro-DNV sensor; and

integrating the micro-DNV sensor with a micro-radio-frequency (RF) source, a micron-sized light source, a fixed bias magnet, and one or more micro-photo detectors to form a micro-DNV assembly,

wherein the micro-DNV assembly is operable to perform vector magnetometry when positioned in an external magnetic field.

2. The method of claim 1, wherein embedding the micron-sized DNV crystal into the bonding material comprises heating a crucible containing the embedded micron-sized DNV crystal and the bonding material.

3. The method of claim 1, further comprising curing the bonding material including the embedded micron-sized DNV crystal by solidifying the bonding material including the embedded micron-sized DNV crystal using ultra-violet (UV) light.

4. The method of claim 1, further comprising affixing the micro-DNV sensor to a silicon chip.

5. The method of claim 4, wherein the micro-RF source is configured to generate RF pulses to stimulate nitrogen-vacancy centers in the micro-DNV sensor, wherein the micro-RF source comprises one of a strip-line resonator, a split ring, or a straight rod dipole, wherein the method further comprises forming the micro-RF source on the silicon chip to surround the micro-DNV sensor when affixed to the silicon chip.

6. The method of claim 4, wherein micron-sized light source comprises a green micron-sized light-emitting diode (LED), wherein the method further comprises forming the green micron-sized LED on the silicon chip.

7. The method of claim 4, wherein at least one of the one or more micro-photo detectors is configured to measure green excitation tight generated by a green micron-sized LED.

8. The method of claim 4, wherein at least some of the one or more micro-photo detectors comprises a red micro-photo detector that is configured to detect fluorescence radiation emitted by stimulated nitrogen-vacancy centers in the micro-DNV sensor, wherein the method further comprises forming the one or more red micro-photo detector on the silicon chip.

9. The method of claim 1, wherein at least one of the one or more micro-photo detectors further comprises a red filter configured to fitter out green tight.

10. The method of claim 8, wherein at least one of the one or more micro-photo detectors further comprises a micro-lens.

11. The method of claim 1, wherein the micro-DNV assembly is operable to measure the external magnetic field with a sensitivity of better than one micro-Tesla.

12. The method of claim 1, wherein the micro-DNV assembly comprises a multilayer structure, and forming the micro-DNV assembly comprises integrating a plurality of layers, wherein each layer includes at least one of the micro-RF source, the micron-sized light source, the fixed bias magnet, or the one or more micro-photo detectors.

13. A method of calibration of a micro-diamond nitrogen-vacancy (micro-DNV) assembly, the method comprising:

applying a plurality of magnetic fields, having known directions with respect to a reference coordinate system, to the micro-DNV assembly;

operating the micro-DNV assembly;

measuring a current generated by a photo detector of the micro-DNV assembly;

estimating a magnetic field vector associated with each of the plurality of magnetic fields, the estimated magnetic field vectors having orientations aligned with a DNV lattice reference frame; and

correlating the estimated magnetic field vectors with the applied plurality of magnetic fields to determine an attitude matrix that defines a transformation from the DNV lattice reference frame into the reference coordinate system.

14. The method of claim 13, wherein determining the attitude matrix comprises processing four pairs of Lorentzian peaks shifted by the applied plurality of magnetic fields and derived from the measured current.

15. The method of claim 13, wherein determining the attitude matrix comprises determining a DNV lattice-to-Cartesian reference axis attitude matrix that relates the DNV lattice reference frame to Lorentzian frequency shift values corresponding to the estimated magnetic field vectors.

16. A vector magnetometer apparatus, the apparatus comprising:

a micron-sized diamond nitrogen-vacancy (micro-DNV) sensor;

a micro-radio-frequency (RF) source configured to generate RE pulses to stimulate nitrogen-vacancy centers in the micro-DNV sensor;

a micron-sized light source;

a fixed bias magnet; and

one or more micro-photo detectors configured to detect fluorescence radiation emitted by stimulated nitrogen-vacancy centers,

wherein the micro-DNV sensor comprises a micron-sized DNV crystal embedded in a cured bonding material, and wherein the micro-DNV assembly is operable to perform vector magnetometry when positioned in an external magnetic field.

17. The apparatus of claim 16, wherein the micro-DNV sensor is affixed to a silicon chip.

18. The apparatus of claim 16, wherein the micro-RE source is configured to generate RF pulses to stimulate nitrogen-vacancy centers in the micro-DNV sensor, wherein the micro-RF source comprises one of a strip-line resonator, a split ring, or a straight rod dipole, wherein the micro-RF source is formed on a chip to surround the micro-DNV sensor.

19. The apparatus of claim 16, wherein the micro-RE source is configured to generate RE pulse sequences by using Ramsey, Hahn echo or Barry timing sequences to attain higher sensitivity and to enable measuring AC varying magnetic fields.

20. The apparatus of claim 16, wherein micron-sized light source comprises a green micron-sized light-emitting diode (LED), wherein the green micron-sized LED is formed on a chip, wherein each of the one or more micro-photo detectors comprises a red micro-photo detector, and wherein the one or more red micro-photo detectors are formed on the chip.

21. The apparatus of claim 20, wherein at least one of the one or more micro-photo detectors is configured to measure green excitation light generated by the green micron-sized LED.

22. The apparatus of claim 20, wherein the green micron-sized LED is configured to generate green light pulse sequences by using Ramsey, Hahn echo or Barry timing sequences to attain higher sensitivity and enable measuring AC varying magnetic fields.

23. The apparatus of claim 16, wherein at least one of the one or more micro-photo detectors further comprises a red filter configured to filter out green light.

24. The apparatus of claim 16, wherein at least one of the one or more micro-photo detectors further comprises a micro-lens.

25. The apparatus of claim 16, wherein the micro-DNV assembly is operable to measure the external magnetic field with a sensitivity of better than one micro-Tesla.

26. The apparatus of claim 16, wherein the micro-DNV assembly comprises a multilayer structure formed by integrating a plurality of layers, wherein each layer includes at least one of the micro-RE source, the micron-sized light source, a fixed bias magnet, or the one or more micro-photo detectors.