1048results about "Magnetic field measurement using magneto-optic devices" patented technology

High-accuracy magnetic measurement is performed by efficiently using nitrogen-vacancy pairs in all orientations. A magnetic measurement apparatus includes a diamond crystal and an image sensor. The diamond crystal has nitrogen-vacancy pairs. The image sensor detects the intensities of fluorescence generated by an exciting light applied to the diamond crystal by using a plurality of pixels. The nitrogen-vacancy pairs of the diamond crystal are made to one-to-one correspond to the pixels. The fluorescence generated by one nitrogen-vacancy pair is received by one pixel made to correspond to the nitrogen-vacancy pair.

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.

A magnetic field measurement system includes at least one magnetometer; and at least one flux concentrator made of a high magnetic permeability material and configured to receive magnetic field signals from a source, to concentrate the magnetic field signals or reorient the magnetic field signals in a preselected direction, and to direct the concentrated or reoriented magnetic field signals toward at least one of the at least one magnetometer. In addition to, or as an alternative to, the flux concentrator, the system can include a passive shield made of the high magnetic permeability material. The system may also include active shielding.

A method of measuring at least one property including a magnetic property of target material is provided. The method includes the step of generating a pump pulse train having one or more pump pulses at a repetition rate along a first propagation path, each pump pulse having a pulse energy density, a laser wavelength within a range of laser wavelengths, and a pulse duration The method further includes the step of irradiating the target material with at least a portion of the one or more pump pulses focused into at least one spot having a spot shape and size so as to cause transient perturbation in the target material. The method still further includes the step of generating at least one probe pulse train having one or more probe pulses at a repetition rate along a second propagation path, each probe pulse having a pulse energy density, a laser wavelength within a range of laser wavelengths, and a pulse duration. The method further includes the step of irradiating the target material with at least a portion of the one or more probe pulses focused into at least one spot having a spot shape and size to obtain one or more reflected probe pulses which are modulated based on the transient perturbation. The method still further includes the step of electronically controlling a time interval between a time at which the target material is irradiated by each of the focused pump pulses and a time at which the target material is irradiated by each of its corresponding focused probe pulses. The method further includes the step of detecting each modulated probe pulse to obtain one or more corresponding signals. The method still further includes the step of processing the one or more signals to obtain one or more measurement signals which represents the at least one property including the magnetic property of the target material.

A light source unit irradiates a gas cell disposed in a measurement region with linearly polarized light in which the direction of travel is a z-axis direction and the vibration direction of an electric field is a y-axis direction. A polarimeter detects optical characteristics of light passing through the gas cell. A magnetic field generator applies an artificial magnetic field, capable of varying an x-axis component, a y-axis component, and a z-axis component, to the measurement region. A calculation control unit generates a plurality of artificial magnetic fields, calculates a magnetization value or a value corresponding to the magnetization value on the basis of the detection results of the polarimeter, and calculates an original magnetic field present in the measurement region, using an artificial magnetic field when the magnetization value or the value corresponding to the magnetization value satisfies a condition for external value.

One embodiment is a magnetic field measurement system that includes at least one magnetometer having a vapor cell, a light source to direct light through the vapor cell, and a detector to receive light directed through the vapor cell; at least one magnetic field generator disposed adjacent the vapor cell; and a feedback circuit coupled to the at least one magnetic field generator and the detector of the at least one magnetometer. The feedback circuit includes at least one feedback loop that includes a first low pass filter with a first cutoff frequency. The feedback circuit is configured to compensate for magnetic field variations having a frequency lower than the first cutoff frequency. The first low pass filter rejects magnetic field variations having a frequency higher than the first cutoff frequency and provides the rejected magnetic field variations for measurement as an output of the feedback circuit.

An FM-NMOR magnetometer and concomitant magnetometry method comprising providing a linearly-polarized pump beam generator, employing a center wavelength approximately equal to a center wavelength of hyperfine peaks, and employing a modulation amplitude in the range HFS-3×LW to HFS.