Abstract: Systems and methods are disclosed for making a quantum network node. A plurality of scoring function F values are calculated for an array of at least two photonic crystal cavity unit cells, each having a lattice constant ? and a hole having a length Hx and a width Hy. A value of ?, a value of Hx, and a value of Hy are selected for which a scoring function value is at a maximum. A waveguide region and the array of at least two photonic crystal cavity unit cells based on the selected values are formed on a substrate. At least one ion between a first photonic crystal cavity unit cell and a second photonic crystal cavity unit cell are implanted and annealed into a quantum defect. A coplanar microwave waveguide is formed on the substrate in proximity to the array of at least two photonic crystal cavity unit cells.

Abstract: A computer system receives a plurality of signals corresponding to first time-series magnetic data generated from a plurality of unshielded magnetometers proximate to the human subject. The first time-series magnetic data corresponds to magnetic fields generated from the human subject. The plurality of signals includes contributions from a biomagnetic field from at least a portion of the subject's organ and a background magnetic field. The computer system synchronizes the first time-series magnetic data to a common clock to generate synchronized time-series magnetic data. The computer system applies one or more filters to the synchronized time-series magnetic data to obtain filtered data. The computer system applies one or more noise reduction techniques to the filtered data to generate updated time-series magnetic data.

Abstract: A computer system receives a plurality of signals corresponding to first time-series magnetic data generated from a plurality of unshielded magnetometers proximate to the human subject. The first time-series magnetic data corresponds to magnetic fields generated from the human subject. The plurality of signals includes contributions from a biomagnetic field from at least a portion of the subject's organ and a background magnetic field. The computer system synchronizes the first time-series magnetic data to a common clock to generate synchronized time-series magnetic data. The computer system applies one or more filters to the synchronized time-series magnetic data to obtain filtered data. The computer system applies one or more noise reduction techniques to the filtered data to generate updated time-series magnetic data.

Abstract: An apparatus for measuring magnetic fields from a subject's organ comprises a plurality of unshielded magnetometers in a three-dimensional arrangement. A respective pair of magnetometers, in the plurality of magnetometers, has a respective known separation. Each magnetometer in the plurality of magnetometers is configured to simultaneously detect a biomagnetic field from at least a portion of the subject's organ and a background magnetic field and output a signal indicative of the detected biomagnetic field and the background magnetic field.

Abstract: Systems and methods are disclosed for making a quantum network node. A plurality of scoring function F values are calculated for an array of at least two photonic crystal cavity unit cells, each having a lattice constant a and a hole having a length Hx and a width Hy. A value of a, a value of Hx, and a value of Hy are selected for which a scoring function value is at a maximum. A waveguide region and the array of at least two photonic crystal cavity unit cells based on the selected values are formed on a substrate. At least one ion between a first photonic crystal cavity unit cell and a second photonic crystal cavity unit cell are implanted and annealed into a quantum defect. A coplanar microwave waveguide is formed on the substrate in proximity to the array of at least two photonic crystal cavity unit cells.

Abstract: A magnetometry apparatus includes an array of magnetometer pixels. Each magnetometer pixel includes an electron spin defect body including a plurality of lattice point defects, and a microwave field transmitter operable to apply a microwave field to the electron spin defect body. The apparatus may also include an optical source configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect bodies from a ground state to an excited state, and a photodetector arranged to receive photoluminescence of a second wavelength emitted from a first electron spin defect body of a first magnetometer pixel of the array of magnetometer pixels. The second wavelength is different from the first wavelength.

Abstract: A traffic monitoring system includes an electron spin defect magnetometer in a vicinity of a roadway, the electron spin defect magnetometer configured to detect magnetic field signals induced by transit entities in the vicinity of the roadway. The electron spin defect magnetometer includes an electron spin defect body including a plurality of lattice point defects, an optical source arranged to excite the plurality of lattice point defects, and a photodetector arranged to receive photoluminescence emitted by the plurality of lattice point defects.

Abstract: A magnetometer includes an electron spin defect body including a plurality of lattice point defects. A microwave field transmitter is operable to apply a microwave field to the electron spin defect body. An optical source is configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect body from a ground state to an excited state. A first optical fiber has an input end optically coupled to the optical source and an output end. The output end is attached to a first face of the electron spin defect body and is arranged to direct the input light into the first face of the electron spin defect body. A second optical fiber has an output end and an input end. A photodetector is optically coupled to the output end of the second optical fiber.

Abstract: A magnetometer includes an electron spin defect body including a plurality of lattice point defects. A microwave field transmitter is operable to apply a microwave field to the electron spin defect body. An optical source is configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect body from a ground state to an excited state. A first optical fiber has an input end optically coupled to the optical source and an output end. The output end is attached to a first face of the electron spin defect body and is arranged to direct the input light into the first face of the electron spin defect body. A second optical fiber has an output end and an input end. A photodetector is optically coupled to the output end of the second optical fiber.

Abstract: Systems and methods are disclosed for making a quantum network node. A plurality of scoring function F values are calculated for an array of at least two photonic crystal cavity unit cells, each having a lattice constant a and a hole having a length Hx and a width Hy. A value of a, a value of Hx, and a value of Hy are selected for which a scoring function value is at a maximum. A waveguide region and the array of at least two photonic crystal cavity unit cells based on the selected values are formed on a substrate. At least one ion between a first photonic crystal cavity unit cell and a second photonic crystal cavity unit cell are implanted and annealed into a quantum defect. A coplanar microwave waveguide is formed on the substrate in proximity to the array of at least two photonic crystal cavity unit cells.

Abstract: A magnetometry apparatus includes an array of magnetometer pixels. Each magnetometer pixel includes an electron spin defect body including a plurality of lattice point defects, and a microwave field transmitter operable to apply a microwave field to the electron spin defect body. The apparatus may also include an optical source configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect bodies from a ground state to an excited state, and a photodetector arranged to receive photoluminescence of a second wavelength emitted from a first electron spin defect body of a first magnetometer pixel of the array of magnetometer pixels. The second wavelength is different from the first wavelength.

Abstract: A magnetometer includes an electron spin defect body including a plurality of lattice point defects. A microwave field transmitter is operable to apply a microwave field to the electron spin defect body. An optical source is configured to emit input light of a first wavelength that excites the plurality of lattice point defects of the electron spin defect body from a ground state to an excited state. A first optical fiber has an input end optically coupled to the optical source and an output end. The output end is attached to a first face of the electron spin defect body and is arranged to direct the input light into the first face of the electron spin defect body. A second optical fiber has an output end and an input end. A photodetector is optically coupled to the output end of the second optical fiber.

Abstract: Systems and methods are disclosed for preparing and evolving atomic defects in diamond. Silicon vacancy spins may be cooled to temperatures equal to or below 500 mK to reduce the influence of phonons. The cooling, manipulation, and observation systems may be designed to minimize added heat into the system. A CPMG sequence may be applied to extend coherence times. Coherence times may be extended, for example, to 13 ms.

Abstract: Systems and methods are disclosed for preparing and evolving atomic defects in diamond. Silicon vacancy spins may be cooled to temperatures equal to or below 500 mK to reduce the influence of phonons. The cooling, manipulation, and observation systems may be designed to minimize added heat into the system. A CPMG sequence may be applied to extend coherence times. Coherence times may be extended, for example, to 13 ms.