Abstract: A magnetometer includes a magnetically isolated chamber having an opening to receive a sample; one or more Optically Pumped Magnetometer (OPM) sensors positioned inside the magnetically isolated chamber; an actuator mounted on a frame, the actuator moving an end portion in and out of the magnetically isolated chamber; and a sample holder coupled to the end portion.

Abstract: Systems and methods of quantum sensing include obtaining information regarding a target signal in electronic spin states of quantum defects in an ensemble of quantum defects, mapping the information regarding the target signal from the electronic spin states of the quantum defects to corresponding nuclear spin states associated with the quantum defects, applying a light pulse to the ensemble of quantum defects to reset the electronic spin states of the quantum defects, and repeating a readout stage a plurality of times within a readout duration. The readout stage includes mapping the information regarding the target signal back from the nuclear spin states to the corresponding electronic spin states and applying a data acquisition readout pulse to optically measure the electronic spin states of the quantum defects.

Abstract: It is an object of the invention to improve processes, apparatuses and systems for measuring a measured variable. To this end, a measured variable is measured in a measuring process on the basis of an NV center as a quantum sensor. The NV center has a plurality of quantum states and is optically excitable on the basis of an occupancy of one of the quantum states into at least one excited state of the quantum states by means of an excitation light. The at least one excited state can decay at least with emission of emission light of the NV center. In the measuring process, the NV center is irradiated by the excitation light, the excitation light having a time periodic modulation, and a respective occupancy probability and/or a respective lifetime of the quantum states depending on the measured variable and the excitation light.

Abstract: An optically pumped, atomic magnetometer incorporates a feedback system for stabilizing the magnetic bias field and suppressing unwanted background fields. The magnetic bias field is applied to a vapor cell containing host atoms of two different species, each of which resonates at a different Larmor frequency when both are subjected to the same magnetic bias field. One species provides the feedback for stabilizing the bias field, thereby creating a stabilizing magnetometer portion that nulls out the unwanted background fields. The other species provides magnetic field detection or signal reception on a radio communication frequency of interest, thereby creating a signal magnetometer portion that permits detection of the signal at the radio communication frequency.

Abstract: An atomic magnetometer, which operates in a communication system using a magnetic signal in a very low frequency (VLF) band, may comprise: a vapor cell comprising one or more alkaline metal atoms; a pump light source configured to provide circularly polarized pump beams to the vapor cell; an irradiation light source configured to provide linearly polarized irradiation beams to the vapor cell; a magnetic signal detecting unit configured to detect a magnetic signal by measuring a polarization rotation angle from the linearly polarized irradiation beam passing through the vapor cell; and a bias magnetic field control unit configured to control a bias magnetic field applied to the vapor cell.

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: Polarized nuclear imaging and spectroscopy systems and methods are disclosed. In some embodiments, nuclei of a radioactive substance are polarized such that the spins of the nuclei are oriented in a specific direction, to generate a polarized radioactive tracer with anisotropic gamma ray emission. The radioactive substance is selected such that the degree of anisotropy is enhanced. A tracer is introduced into a living subject for delivery to a target area of interest in the subject. The tracer is delivered such that nuclear spin relaxation of the tracer is inhibited during transport of the tracer to the target area of interest. Gamma rays from the gamma ray emission are detected, and based on the detected gamma rays and properties associated with the anisotropic gamma ray emission, imaging data and/or spectroscopic data are obtained that are associated with the tracer in the subject.

Abstract: Disclosed herein is a method of detecting a material response. The method includes providing an oscillating primary magnetic field to cause as ample to produce a secondary magnetic field. The method also includes reducing the effect on an atomic magnetometer of components of the primary and secondary magnetic fields in a direction substantially orthogonal to a surface of the sample. The method also includes detecting the secondary magnetic field with the atomic magnetometer to detect the material response.

Abstract: The inventive system for analyzing electromagnetic radiation comprises: an enclosure filled with gas containing atoms of a known type, at least one light source emitting light capable of exciting the atoms of the known type in the gas, a source of the electromagnetic radiation to be analyzed arranged such that the emitted electromagnetic radiation acts on the atoms of the known type in the gas, and a sensor for capturing light emitted by and/or passed through the gas. Further, the system comprises an electrical field source and/or magnetic field source configured to establish a predefined electrical field and/or magnetic field acting on the atoms of the known type in the gas. The light captured by the sensor reflects a response of the atoms of the known type in the gas on the electrical field and/or the magnetic fields, the light from the at least one light source, and the electromagnetic radiation to be analyzed.

Abstract: An integrated sensor includes a sensor cell, a signal source, an input optical rotator, and a signal detector. The integrated sensor includes a positioner for a signal-processing component. The positioner may be a linear positioner for the signal-processing component, such as a signal source or a signal detector, or may be a rotational positioner for the signal-processing component, such as a polarizer or a polarized signal source. The signal-processing component is located on a signal path of the integrated sensor. A method of adjusting a linear position or rotational position of a signal-processing component is also disclosed. A linear position or a rotational position of the signal-processing component may be adjusted to improve performance of the integrated sensor.

Abstract: A method for atom-based closed-loop control includes exciting atoms of a gas into one or more Rydberg states, applying one or more signal processing functions to the one or more Rydberg states, and regulating a characteristic of the applied one or more signal processing functions based on, at least in part, a response of the one or more Rydberg states to the one or more signal processing functions. A system for internal quantum-state-space interferometry includes an atomic receiver, an interferometric pathway, and a detector. The interferometer includes an atomic vapor with first atomic states and second atomic states. The interferometric pathway from RF phases between the first and second atomic states is closed by a quantum-state-space. The detector is configured to detect a readout of an interferometric signal. Embodiments include atom-based automatic level control, baseband processors, phase-locked loops, voltage transducers, raster RF imagers and waveform analyzers.

Abstract: A method is provided for sensing a magnetic field in a magnetic gradiometer of the kind in which pump light and light constituting an optical carrier traverse first and second atomic vapor cells that contain host atoms and that are separated from each other by a known distance. According to such method, the host atoms are prepared in a coherent superposition of two quantum states that differ in energy by an amount that is sensitive to an ambient magnetic field. Modulation of the optical carrier in the respective cells gives rise to sidebands that interfere to generate a beat frequency indicative of the magnetic field gradient. The host atoms are prepared at least in a mode that allows measurement of ambient magnetic field components perpendicular to the axis of the pump light. In such mode, the host atoms are spin-polarized by pump light while subjected to a controlled magnetic field directed parallel to the pump beam, and then the controlled magnetic field is adiabatically extinguished.

Abstract: A system can include: a superconducting or permanent magnet; a high field portion corresponding to the superconducting or permanent magnet, wherein the high field has a range of 0.1-20 T; a low field portion positioned outside of the superconducting or permanent magnet, wherein the low field has a range of 0.01 nT-100 mT; a shuttling mechanism configured to deliver a sample between the low field portion and the high field portion; and a polarization sub-assembly configured to hyperpolarize the sample while the sample is within the low field portion. A device can be configured to cause nuclear spin hyperpolarization in diamond particles such that the hyperpolarization is transferable to at least one of an external liquid or an external solid.

Abstract: A magnetic field measurement system 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 a first feedback loop that includes a first low pass filter with a first cutoff frequency and a second feedback loop that includes a second low pass filter with a second cutoff frequency. The first and second feedback loops are configured to compensate for magnetic field variations having a frequency lower than the first or second cutoff frequency, respectively.

Abstract: A magnetic field measurement device and a magnetic field measurement method based on solid-state spins are provided. Zeeman splitting between electron energy levels of electrons of a magnetic sensitive unit is different under the action of external magnetic fields having different intensities. Continuous excitation and manipulation is applied to the electrons by means of a control field and control laser, so that spins of a system can reach a balanced state. The spin population of the system is influenced by the external magnetic fields. Therefore, fluorescence signals with intensities changing with the spin population of the system can be obtained, and fluorescent signals having different intensities can be obtained according to the different intensities of the external magnetic fields.

Abstract: A magnetometer includes a vapor cell having at least one wall, a chamber defined by the at least one wall, and alkali metal atoms disposed in the chamber to produce an alkali metal vapor in the chamber, wherein the at least one wall includes an oxide-containing interior surface; and an anti-relaxation coating disposed on the oxide-containing interior surface of the at least one wall of the vapor cell, wherein the anti-relaxation coating is a reaction product of the oxide-containing interior surface of the at least one wall with at least one mono- or dichlorosilane compound.

Abstract: One example includes a magnetometer that includes a sensor cell comprising alkali metal vapor and a magnetic field generator system that generates predetermined AC magnetic fields through the sensor cell. The magnetometer also includes a laser system to provide optical pump and probe beams through the sensor cell in a pulsed manner to facilitate precession of the alkali metal vapor and to provide a detection beam corresponding to the optical probe beam exiting the sensor cell. The detection beam exhibits an optical property corresponding to a modified precession of the alkali metal vapor based on the predetermined AC magnetic fields and an external magnetic field. The magnetometer also includes a detection system to monitor the detection beam to detect the modified precession of the alkali metal vapor to calculate scalar and vector components of the external magnetic field based on the plurality of predetermined AC magnetic fields.

Abstract: A magnetic field generator includes a first planar substrate, a second planar substrate positioned opposite to the first planar substrate and separated from the first planar substrate by a gap, a first wiring set on the first planar substrate, a second wiring set on the second planar substrate, and one or more interconnects between the first planar substrate and the second planar substrate. The one or more interconnects electrically connect the first wiring set with the second wiring set to form a continuous electrical path. The continuous electrical path forms a conductive winding configured to generate, when supplied with a drive current, a first component of a compensation magnetic field configured to actively shield a magnetic field sensing region located in the gap from ambient background magnetic fields along a first axis that is substantially parallel to the first planar substrate and the second planar substrate.

Abstract: A sensing array includes a plurality of pixels, one pixel of which includes: a sensor, the sensor including a first electrode, a second electrode, and an atomic defect site configured to be excited by light of a first frequency; a light source below the sensor and configured to emit light of the first frequency toward the defect site; and a radio frequency (RF) source below the sensor and configured to provide a first voltage to the first electrode, a second voltage to the second electrode, and an RF signal to the sensor, wherein the sensor is configured to sense a magnitude of a physical parameter by generating a photocurrent corresponding to a magnitude of a physical parameter and a differential between the first and second voltages, when excited by the light of the first frequency and affected by the RF signal.

Abstract: High-sensitivity multi-channel atomic magnetometers are described. Methods for operating multi-channel atomic magnetometers are also described. Moreover, devices incorporating a plurality of multi-channel atomic magnetometers are described. A multi-channel atomic magnetometer may use the spin-exchange relaxation-free (SERF) technique. A multi-channel atomic magnetometer may achieve multi-channel operation in a single module, reducing the cost of sensors. A multi-channel atomic magnetometer may be a 16-channel atomic magnetometer. A multi-channel atomic magnetometer may include a single large vapor cell including alkali-metal atoms and at least one buffer gas that restricts motion of atomic spins of the alkali-metal atoms, thereby making relatively small internal cell volumes act as a multiple independent local sensing channels.

Abstract: A vector magnetometer comprises a cell to be filled with an atomic gas, an optical source and a photo-detection device. The optical source is configured to emit towards the cell: a first and a second optical beam, called probe beams, that are polarised linearly, a third optical beam, called the pump beam, linearly polarised. The polarisation directions of the probe beams and the polarisation direction of the pump beam are not coplanar. The photo-detection device is configured to receive light from the probe beams that have passed through the cell. The probe beams can have the same propagation direction. The polarisation direction of the pump beam can form an angle of 45°±10° with the polarisation direction of each of the probe beams.

Abstract: A cell module used for a photoexcitation magnetic sensor includes a cell in which an alkali metal is enclosed, a heater which is disposed close to the cell to heat the alkali metal, and a case which forms a decompression region accommodating the cell and the heater.

Abstract: 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.

Abstract: A laser system has a fiber cable, a pump enclosure connected to the fiber cable outside of the pump enclosure, and a laser-head enclosure connected to the fiber cable disposed outside of the laser-head enclosure. The pump enclosure houses a fiber-coupled laser diode configured to produce and convey pump light through the pump enclosure out to the fiber cable. The laser-head enclosure houses a crystal. The pump light, when produced by the laser diode, propagates out from the pump enclosure through the fiber cable into the laser-head enclosure and into the crystal. The crystal produces a laser beam in response to the pump light. The integrated fiber of the laser diode, the fiber cable, and internal fiber of the laser-head enclosure, through which the pump light propagates, may be single-mode fibers, to achieve superior laser system performance with lower frequency and intensity noise than pumping through multimode fibers.

Abstract: An array of optically pumped magnetometers includes an array of vapor cells; and an array of beam splitters. The array of beam splitters is arranged into columns, including a first column, and rows. Each row and each column includes at least two of the beam splitters. The array of beam splitters is configured to receive light into the first column of the array and to distribute that light from the first column into each of the rows and to distribute the light from each of the rows into a plurality of individual light beams directed toward the vapor cells.

Abstract: A gyroscope package, system and method for use in a downhole tool suitable are provided. The gyroscope package, system and method includes a housing coupleable with a downhole tool, a gyroscope body within the housing, and an inductive-type MEMS gyroscope. The MEMS gyroscope includes a magnetic shield disposed around the inductive-type MEMS gyroscope to magnetically shield the inductive-type MEMS gyroscope.

Abstract: A magnetic field measurement system includes an array of magnetometers; at least one magnetic field generator configured to generate a compensation field across the array of magnetometers; and a controller coupled to the magnetometers and the at least one magnetic field generator and configured for adjusting a dynamic range and sensitivity of the array by adjusting a spatial variation of the compensation field to alter which of the magnetometers of the array operate in a measurement mode. Another magnetic field measurement system utilizes at least one magnetometer instead of the array. The controller is configured for adjusting a dynamic range and sensitivity of the array by adjusting a spatial variation of the compensation field to alter which of multiple domains within the at least one magnetometer operate in the measurement mode.

Abstract: The Zeeman shift of electronic spins in nitrogen-vacancy (NV) centers in diamond has been exploited in lab-scale instruments for ultra-high-resolution, vector-based magnetic sensing. A quantum magnetometer in CMOS utilizing a diamond-nanocrystal layer with NVs or NV-doped bulk diamond on a chip-integrated system provides vector-based magnetic sensing in a compact package. The system performs two functions for the quantum magnetometry: (1) strong generation and efficient delivery of microwave for quantum-state control and (2) optical filtering/detection of spin-dependent fluorescence for quantum-state readout. The microwave delivery can be accomplished with a loop inductor or array of wires integrated into the chip below the nanodiamond layer or diamond. And the wire array can also suppress excitation light using a combination of plasmonic and (optionally) Talbot effects.

Abstract: Detection of intravascular plaque in OCT images is carried out by obtaining images of vascular tissue from a vascular component by OCT either in a static mode of a single image or in a dynamic mode where the images are obtained by scanning. The method acts by dividing the OCT image into different regular regions, calculating different texture features for each of the above regions with a reduced set of less than a full set of the 26 Haralick textural features, using a clustering algorithm to segment the image defined by its texture features calculated above into different regions and transforming the segmented image back from its representation using texture features to its space-domain representation. The method uses three or four texture features where the reduced sets can be f1, f 2, and f14 (ASM at 0°, Inertia at 0° and ASM at 90°).

Abstract: A vector magnetometer comprising a cell filled with an atomic gas subjected to an ambient magnetic field, an optical pumping source capable of emitting a pump beam tuned to a pumping wavelength towards the cell and a parametric resonance detection device receiving a probe beam that has passed through the cell, the probe beam being identical to or different from the pump beam. The magnetometer also comprises a polarisation device configured so as to simultaneously or alternately confer linear polarisation and circular polarisation to the pump beam emitted towards the cell. And the detection device comprises an optical set up configured to separate, from the probe beam that has passed through the cell, optical signals carrying respectively information about an alignment state of the atoms from information about an orientation state of the atoms.

Abstract: This disclosure relates to determining a spatial configuration of multiple nuclei. An electron dipole generates a spatially varying magnetic field such that each of the multiple nuclei is resonant at a respective resonance frequency defined by the magnetic field at a location of that nucleus. A first signal generator generates a first signal at a first signal frequency such that, as a result of dipole-dipole interaction between the electron dipole and a subset of the multiple nuclei that are resonant at the first signal frequency, a phase of the electron dipole is indicative of a number of nuclei that are resonant at the first signal frequency. A readout module determines the phase of the electron dipole, and determines the spatial configuration of the multiple nuclei based on the phase of the electron dipole. As a result of the high spatial resolution of the sensing the nuclear structure of molecules can be determined with low noise.

Abstract: One example includes a magnetometer system that includes a sensor cell comprising alkali metal vapor and at least one measurement zone corresponding to a three-dimensional spatial region within the sensor cell. The system also includes a laser system configured to provide an optical pump beam through the sensor cell in a pulsed manner to facilitate precession of the alkali metal vapor in response to an external magnetic field and to provide an optical probe beam through the sensor cell in a pulsed manner based on a precession frequency of the alkali metal vapor. The system also includes a detection system configured to detect the precession of the alkali metal vapor in response to a detection beam corresponding to the optical probe beam exiting the sensor cell and to calculate an amplitude and direction of the external magnetic field based on the detected precession of the alkali metal vapor.

Abstract: One embodiment of the invention includes a magnetometer system. The system includes a sensor cell comprising alkali metal particles and at least one nuclear spin isotope. The system also includes a probe laser to provide a probe beam through the sensor cell to generate a detection beam, and a magnetic field system to generate magnetic fields through the sensor cell. The system also includes a detection system to implement detection of an external magnetic field based on characteristics of the detection beam in response to precession of the at least one nuclear spin isotope based on the magnetic fields. The system further includes a calibration controller configured to calibrate the magnetometer system based on implementing predetermined changes to the magnetic fields and monitoring the detection beam in a feedback manner.

Abstract: An optical magnetometer comprising: a response frequency measurement unit comprising a vapor cell, a pulsed-mode pump laser and a probe laser; and a computing unit configured to compute a magnetic field change based on a difference between at least two temporally-distinct response frequency values received from the frequency measurement unit. Optionally, the response frequency measurement unit is magnetically non-shielded.

Abstract: A method for quantum metrology using stable non-equilibrium states of quantum matter, such as many-body quantum spin systems, is disclosed. The approach can utilize quantum correlations in such many-body quantum spin systems stabilized by strong interactions and periodic driving for reduction of noise. As an example, an exemplary protocol to perform Floquet enhanced measurements of an oscillating magnetic field in Ising-interacting spin systems is provided. These approaches allow for circumvention of the interaction-induced decoherence associated with high density spin ensembles and is robust to the presence of noise and imperfections. The protocol is applicable to nanoscale magnetic sensing and other precision measurements.

Abstract: A cesium optical pump detector for buried and abandoned chemical weapons of Japan is provided, comprising a pumping light generation module, a first optical module, a magnetic resonance module, a photoelectric detection module, and a signal processing module. The signal processing module includes an amplifying and filtering unit, a self-oscillation unit, a measuring unit, and a calculating unit connected in sequence. The amplifying and filtering unit comprises a first band-pass filter configured to coarsely measure a frequency of the electrical signal and a second band-pass filter configured to finely measure the frequency of the electrical signal. The self-oscillation unit comprises a first phase shifter connected to the first band-pass filter and a second phase shifter connected to the second band-pass filter. In the present disclosure, the intensity of a magnetic field detected can be finely measured, so that the ACWs can be found efficiently and accurately.

Abstract: A magnetic field sensor assembly includes a first radio frequency (RF) element; a second RF element; an RF feed cable operably connected to the first RF element and the second RF element that provides an RF signal to the first RF element and the second RF element; and a magneto-optical defect center material located between the first RF element and the second RF element. The first RF element and the second RF element generate a microwave signal that is uniform over the magneto-optical defect center material. The magneto-optical defect center material may be a nitrogen-vacancy center diamond.

Abstract: A nonlinear terahertz (THz) spectroscopy technique uses a sample illuminated by two THz pulses separately. The illumination generates two signals BA and BB, corresponding to the first and second THz pulse, respectively, after interaction with the sample. The interaction includes excitation of at least one ESR transition in the sample. The sample is also illuminated by the two THz pulses together, with an inter-pulse delay ?, generating a third signal BAB. A nonlinear signal BNL is then derived via BNL=BAB?BA?BB. This nonlinear signal BNL can be then processed (e.g., Fourier transform) to study the properties of the sample.

Abstract: In a general aspect, a quantum logic gate is performed in a quantum computing system. In some cases, a pair of qubits are defined in a quantum processor; the pair of qubits can include a first qubit defined by a first qubit device in the quantum processor and a second qubit defined by a tunable qubit device in the quantum processor. A quantum logic gate can be applied to the pair of qubits by communicating a control signal to a control line coupled to the tunable qubit device. The control signal can be configured to modulate a transition frequency of the tunable qubit device at a modulation frequency, and the modulation frequency can be determined based on a transition frequency of the first qubit device.

Abstract: A magnetometer for use with a sample including an atomic vapor includes a cell containing the sample such as a multipass cell including a first mirror element and a second mirror element configured so that an incoming light beam injected into the container will reflect multiple times between the first mirror element and the second mirror element. A polarized pump light source is configured to transmit pump light through the cell and pump the sample. A polarized probe light source configured to transmit probe light through the cell and probe the sample. A detector configured to detect a polarization angle or intensity of the probe light transmitted through the sample. A processor may be configured to calculate a precession frequency of the sample based on a first probe light pulse and a frequency correction based on a second probe light pulse.

Abstract: A method for magnetic detection includes (a) providing optical excitation to a magneto-optical defect center material using an optical light source, (b) providing pulsed radio frequency (RF) excitation to the magneto-optical defect center material using a pulsed RF excitation source, and (c) receiving an optical signal emitted by the magneto-optical defect center material using an optical detector, such that the magneto-optical defect center material includes a plurality of magneto-optical defect centers and that (a) and (c) occur during (b).

Abstract: A magnetism measuring device includes a light source unit, a diamond crystal and an image sensor. The light source unit irradiates the diamond crystal with an excitation light, and irradiates the image sensor with a fluorescent light generated by the diamond crystal. The diamond crystal includes a plurality of nitrogen-vacancy pairs. The image sensor detects an intensity of the fluorescent light, which is generated from the diamond crystal, by a plurality of pixels. The image sensor and the light source unit are disposed so as to be contained within a projection area of the diamond crystal.

Abstract: A system for magnetic detection of an external magnetic field is described. The system includes a nitrogen vacancy (NV) diamond material having a plurality of crystallographic axes, a radio frequency (RF) excitation source, an optical excitation source, an optical detector, and a controller. The RF radio frequency excitation source is configured to provide RF excitations to the NV diamond material to excite electron spin resonances corresponding to the RF excitations. The controller determines the spectral position corresponding to some of the electron spin resonances, determines a measured four-dimensional projection of a magnetic field based on the determined spectral positions of a subset of all of the plurality of spin resonances, where the number of spin resonances in the subset is one half of a total number of the spin resonances, and determines an estimated three-dimensional magnetic field based on the measured four-dimensional magnetic field projections.

Abstract: A quantum interference device has an atomic cell which has alkali metal atoms disposed within. A light source emits light to excite the alkali metal atoms in the atomic cell. An optical element is disposed between the light source and the atomic cell, and enlarges the radiation angle of light emitted from the light source. A light detector detects light transmitted through the atomic cell.

Abstract: The disclosure relates to a magnetometer sensor with negatively charged nitrogen-vacancy centers in diamond. One example embodiment is a magnetometer sensor. The magnetometer sensor includes a diamond crystal with one or more negatively charged nitrogen-vacancy centers. The magnetometer sensor also includes one or more light sources. Further, the magnetometer sensor includes an electrode. In addition, the magnetometer sensor includes a read-out module. The read-out module includes a read-out circuit configured to read-out a photocurrent from the electrode and a lock-in amplifier. The lock-in amplifier includes a first input, a second input, and an output. The magnetometer sensor additionally includes a microwave source configured to apply a microwave field to the negatively charged nitrogen-vacancy centers. The microwave source includes a microwave generator for generating continuous wave microwaves and a microwave modulator configured to modulate the continuous wave microwaves.

Abstract: A magnetic resonance imaging (MRI) radio frequency (RF) coil comprising an LC circuit including at least one series capacitor, and a decoupling circuit connected in parallel to the LC circuit. The decoupling circuit is configured to decouple the MRI RF coil from one or more other MRI RF coils using passive decoupling upon the production of an induced voltage in the decoupling circuit, or to actively decouple the MRI RF coil from one or more other MRI RF coils upon the insertion of a DC bias into the decoupling circuit. The decoupling circuit includes a pair of fast switching PIN diodes including a first PIN diode connected antiparallel with a second PIN diode, the second PIN diode connected in series with a first capacitor. The decoupling circuit further includes an inductor connected in series with the pair of fast switching PIN diodes and the capacitor.

Abstract: Magnetometers, atomic sensors and related systems, methods and devices are disclosed. In one configuration, an assembly for use in a high-sensitivity atomic sensor can include an alkali vapor cell, at least one illumination source configured to emit light when activated, the emitted light having a first predetermined range of wavelengths, a light collector capable of collecting light in the first predetermined range of wavelengths, and a plurality of optical elements arranged such that (a) light emitted from the at least one illumination source is directed to the alkali vapor cell, and (b) light emerging from the alkali vapor cell is directed to the light collector.

Abstract: One embodiment of the invention includes a magnetometer system. The system includes a sensor cell comprising alkali metal particles and a probe laser configured to provide a probe beam through the sensor cell. The system also includes a detection system configured to implement nuclear magnetic resonance (NMR) detection of a vector magnitude of an external magnetic field in a first of three orthogonal axes based on characteristics of the probe beam passing through the sensor cell and to implement electron paramagnetic resonance (EPR) detection of a vector magnitude of the external magnetic field in a second and a third of the three orthogonal axes based on the characteristics of the probe beam passing through the sensor cell. The system further includes a controller configured to calculate a scalar magnitude of the external magnetic field based on the magnitude of the external magnetic field in each of the three orthogonal axes.

Abstract: A method is presented for measuring the electric field of electromagnetic radiation using the spectroscopic responses of Rydberg atoms to the electromagnetic radiation field. The method entails implementing quantitative models of the Rydberg atom response to the electromagnetic radiation field to provide predetermined atomic properties or spectra for field amplitudes and or frequencies of interest, spectroscopically measuring the response (spectrum) of Rydberg atoms exposed to an unknown electromagnetic radiation field, and obtaining the electric field amplitude and/or frequency of the unknown electromagnetic radiation by using features extracted from the measured spectrum and comparing them to features in a predetermined spectrum among the set of predetermined spectra.

Abstract: There is provided an optically pumped magnetometer, in which a pump light having a first wavelength to spin-polarize a first alkali-metal atom group is made to enter a cell containing the first alkali-metal atom group and a second alkali-metal atom group interacting via spin exchange with the first alkali-metal atom group, a probe light having a second wavelength different from the first wavelength to measure spin polarization of the second alkali-metal atom group is made to enter the cell to form the same optical axis as the pump light, a wavelength discrimination unit is provided to discriminate between the pump light and the probe light that passed through the cell depending on a different in wavelength, and the rotation angle of a polarization plane of the probe light that passed through the cell is measured so that the degree of flexibility of the device layout can be increased.