Magneto-optical detecting apparatus and methods

• US 10,677,953 B2
• Filed: 05/31/2017
• Issued: 06/09/2020
• Est. Priority Date: 05/31/2016
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Stetson, John B., Manickam, Arul, Kaup, Peter G., Bruce, Gregory Scott, Lew, Wilbur, Hahn, Joseph W., Luzod, Nicholas Mauriello, Jackson, Kenneth Michael, Swett, Jacob Louis, Bedworth, Peter V., Sinton, Steven W., Huynh, Duc, Dimario, Michael John, Hansen, Jay T., Mandeville, Andrew Raymond, Fisk, Bryan Neal, Villani, Joseph A., Russo, Jon C., Coar, David Nelson, Miller, Julie Lynne, Kottapalli, Anjaney Pramod, Montgomery, Gary Edward, Shaw, Margaret Miller, Sekelsky, Stephen, Krause, James Michael, Meyer, Thomas J.
• Primary Examiner(s): Yeninas, Steven L
• Application Number:
  US15/610,526
• Publication Number:
  US 20170343695A1
• Time in Patent Office: 1,105 Days
• Field of Search: 324202, 324244, 3242441, 324260, 324304, 324305
• CPC Class Codes: G01R 33/032 using magneto-optic devices, e.g. Faraday or Cotton-Mouton effect
• CPC Class Codes: G01R 33/26 using optical pumping
• CPC Class Codes: G01V 3/101 by measuring the impedance of the search coil; by measuring features of a resonant circuit comprising the search coil measuring impedance or characteristics derived therefrom G01R27/00, e.g. quality factor G01R27/26
• CPC Class Codes: G01V 3/14 operating with electron or nuclear magnetic resonance

Abstract

A system for magnetic detection includes a magneto-optical defect center material including at least one magneto-optical defect center that emits an optical signal when excited by an excitation light; a radio frequency (RF) exciter system configured to provide RF excitation to the magneto-optical defect center material; an optical light source configured to direct the excitation light to the magneto-optical defect center material; and an optical detector configured to receive the optical signal emitted by the magneto-optical defect center material.

Claims

1. A system comprising:

a magneto-optical defect center magnetometer comprising;

a magneto-optical defect center element;

a collection device;

an optical light source comprising;

a readout optical light source configured to provide continuous optical excitation to the magneto-optical defect center element to transition spin states of relevant magneto-optical defect center electrons in the magneto-optical defect center element to an excited state; and

a reset optical light source configured to provide, at a defined interval concurrent to the provision of the continuous optical excitation, optical light to the magneto-optical defect center element to reset the spin states in the magneto-optical defect center element from the excited state to a ground state, wherein the reset optical light source provides a higher power light than the readout optical light source; and

a radio frequency (RF) excitation source configured to provide RF excitation to the magneto-optical defect center element, the RF excitation source comprising a plurality of coils adjacent the magneto-optical defect center element, the coils each having a spiral shape.

2. The system of claim 1, wherein the magneto-optical defect center magnetometer further comprises:

a half-wave plate; and

a mounting base configured such that the half-wave plate can rotate relative to the mounting base around an axis of the half-wave plate.

3. The system of claim 2, wherein the magneto-optical defect center magnetometer further comprises:

a base structure; and

an adjustment mechanism configured to adjust a position of a plurality of lenses relative to at least one of the readout optical light source or the reset optical light source.

4. The system of claim 3, wherein the magneto-optical defect center magnetometer further comprises:

an optical detection circuit including the collection device, and configured to;

activate a switch between a disengaged state and an engaged state;

receive, via one of the readout optical light source or the reset optical light source, a light signal comprising a high intensity signal; and

cause or the optical detection circuit to operate in a non-saturated state responsive to the activation of the switch.

5. The system of claim 4 further comprising:

a substrate comprising an electron spin center;

a complementary moiety attached to a paramagnetic ion, which is attached to the substrate; and

a processor configured to identify a target molecule based on an identity of the complementary moiety and a detected magnetic effect change,

wherein the magneto-optical defect center magnetometer is arranged to detect the magnetic effect change of the electron spin center caused by a change in position of the paramagnetic ion due to the target molecule passing by the complementary moiety.

6. The system of claim 4 further comprising:

a plurality of unmanned aerial systems (UASs), wherein the magneto-optical defect center magnetometer is one of a plurality of magneto-optical defect center magnetometers, wherein each of the plurality of magneto-optical defect center magnetometers is attached to a respective one of the UASs, wherein each of the plurality of magneto-optical defect center magnetometers is configured to generate a vector measurement of a magnetic field; and

a central processing unit in communication with each of the plurality of magneto-optical defect center magnetometers, wherein the central processing unit is configured to;

receive, from the plurality of magneto-optical defect center magnetometers, a first set of vector measurements and corresponding locations, wherein the corresponding locations indicate where a respective magnetometer of the plurality of magneto-optical defect center magnetometers was when the respective vector measurement of the first set of vector measurements was taken;

generate a magnetic baseline map using the first set of vector measurements;

receive, from the magneto-optical defect center magnetometer of the plurality of magneto-optical defect center magnetometers, a first vector measurement and a first corresponding location;

compare the first vector measurement with the magnetic baseline map using the first corresponding location to determine a first difference vector; and

determine that a magnetic object is in an area corresponding to the area of the magnetic baseline map based on the first difference vector.

7. The system of claim 4 further comprising:

a plurality of buoys, wherein the magneto-optical defect center magnetometer is one of a plurality of magneto-optical defect center magnetometers, wherein each of the plurality of magneto-optical defect center magnetometers is attached to a respective one of the buoys, wherein each of the plurality of magneto-optical defect center magnetometers is configured to generate a vector measurement of a magnetic field; and

a central processing unit in communication with each of the plurality of magneto-optical defect center magnetometers, wherein the central processing unit is configured to;

receive, from the plurality of magneto-optical defect center magnetometers, a first set of vector measurements and corresponding locations, wherein the corresponding locations indicate where a respective magnetometer of the plurality of magneto-optical defect center magnetometers was when the respective vector measurement of the first set of vector measurements was taken;

generate a magnetic baseline map using the first set of vector measurements;

receive, from the magneto-optical defect center magnetometer of the plurality of magneto-optical defect center magnetometers, a first vector measurement and a first corresponding location;

compare the first vector measurement with the magnetic baseline map using the first corresponding location to determine a first difference vector; and

determine that a magnetic object is in an area corresponding to the area of the magnetic baseline map based on the first difference vector.

8. The system of claim 4, wherein the magneto-optical defect center magnetometer is one of a plurality of magneto-optical defect center magnetometers of an array of magnetometers configured to capture magnetic images, wherein the magnetic images comprises a first magnetic image of a well pay zone, and a second magnetic image comprises a magnetic image captured after a well bore is padded with a fluid, the first magnetic image comprising a baseline magnetic profile including Earth'"'"'s magnetic field, and remnant sources of magnetism in the well pay zone, the first magnetic image comprising a first set of one of more vector measurements using the array of magnetometers, the second magnetic image comprising a second set of one of more vector measurements using the array of magnetometers;

and

a processor configured to provide a background image based on the first and the second magnetic images,

wherein;

a third magnetic image is captured by the array of magnetometers after a doped proppant is injected into a stage, the third magnetic image comprising a third set of one of more vector measurements using the array of magnetometers, and

the processor is configured to process the third magnetic image to subtract the background and to obtain information regarding distribution of the fluid and the proppant in the stage.

9. The system of claim 4, wherein the magneto-optical defect center magnetometer is configured to sense a modulated magnetic field comprising multiple channels, the system further comprising:

a signal processor configured to demodulate each channel of the multiple channels of the sensed modulated magnetic field,

wherein;

each channel of the modulated magnetic field comprises an optimized variable amplitude triangular waveform, the magnetic field sensor detecting a direction of a polarization of a B-field vector corresponding to a channel for a transmitter using a transmitted MAX and OFF symbol of the modulated magnetic signal, the signal processor configured to demodulate the channel of the sensed modulated magnetic field using the detected direction.

10. The system of claim 4 further comprising:

one or more electronic processors configured to;

receive a magnetic vector of a magnetic field detected by the magneto-optical defect center magnetometer; and

determine a presence of a current source based upon the magnetic vector; and

a navigation control configured to navigate a vehicle based upon the presence of the current source and the magnetic vector.

11. The system of claim 4, wherein the magneto-optical defect center magnetometer is a first magnetic sensor, the system further comprising:

a position encoder component comprising a plurality of uniform magnetic regions, wherein the uniform magnetic regions have a uniform spacing therebetween,

a second magnetic sensor, wherein the magnetic sensor and the second magnetic sensor are separated by a distance that is less than the uniform spacing between the uniform magnetic regions, and

a controller configured to;

determine a direction and magnitude of a change in position of the position encoder component based on the output of the first magnetic sensor and the second magnetic sensor.

12. The system of claim 4, wherein the magneto-optical defect center magnetometer is configured to simultaneously measure the magnitude of a modulated magnetic field in a plurality of directions, the system further comprising:

a processor operatively coupled to the magneto-optical defect center magnetometer, wherein the processor is configured to;

receive, from the magneto-optical defect center magnetometer, a time-varying signal corresponding to the modulated magnetic field,

determine a plurality of transmission channels based on the time-varying signal, and

monitor the plurality of transmission channels to determine data transmitted on each of the plurality of transmission channels.

13. The system of claim 4 further comprising:

a processor operatively coupled to the magneto-optical defect center magnetometer and configured to;

monitor a magnetic field magnitude sensed by the magneto-optical defect center magnetometer;

determine a change in the magnetic field sensed by the magneto-optical defect center magnetometer; and

determine that a length of a material comprises a defect based at least on the change in the magnetic field.

14. The system of claim 4 further comprising:

a ferro-fluid configured to deform when contacted by sound waves;

a magnet configured to activate the ferro-fluid; and

one or more processors,

wherein the magneto-optical defect center magnetometer is configured to detect a magnetic field of the ferro-fluid and to detect movement of the ferro-fluid, and

wherein the one or more processors is configured to translate movement of the ferro-fluid into acoustic data associated with the sound waves.

15. The system of claim 1, wherein the RF excitation source is further configured to provide at least two pulses of the RF excitation between two pulses of the optical light by the reset optical light source provided at the defined interval and during the continuous provision of the readout optical light source by the readout optical light source.

16. The system of claim 1, wherein the RF excitation source is further configured to provide the RF excitation at a second defined interval relative to the defined interval at which the optical light is provided by the reset optical light source.

17. The system of claim 16, wherein the magneto-optical defect center magnetometer further comprises an optical detection circuit including the collection device, configured to receive, via one of the readout optical light source or the reset optical light source, a light signal subsequent to application of the RF excitation to use to measure a magnetic field of the magneto-optical defect center element.

18. A magneto-optical defect center magnetometer comprising:

a magneto-optical defect center element;

a collection device;

an optical light source comprising;

a readout optical light source configured to provide continuous optical excitation to the magneto-optical defect center element to transition spin states of relevant magneto-optical defect center electrons in the magneto-optical defect center element to an excited state; and

a reset optical light source configured to provide, at a defined interval and concurrent to the provision of the continuous optical excitation, optical light to the magneto-optical defect center element to reset the spin states in the magneto-optical defect center element from the excited state to a ground state,

wherein the reset optical light source provides a higher power light than the readout optical light source; and

an RF exciter system comprising;

a RF source;

a controller configured to control the RF source,

the RF input;

a RF ground;

a microstrip line electrically connected to the RF input and short circuited to the RF ground adjacent the magneto-optical defect center material,

wherein controller is configured to control the RF source such that a standing wave RF field is created in the magneto-optical defect center material.

19. The magneto-optical defect center magnetometer of claim 18, wherein the controller is further configured to control the RF source to provide an RF excitation at a second defined interval relative to the defined interval at which the optical light is provided by the reset optical light source.

20. The magneto-optical defect center magnetometer of claim 19, wherein the controller is further configured to measure a magnetic field of the magneto-optical defect center element based on a light signal received subsequent to application of the RF excitation at the second defined interval.