Abstract: An illustrative system includes a sensor component and a controller conductively coupled by way of a first wire and a second wire in a twisted pair configuration. The controller includes a driver configured to drive the sensor component by way of the first and second wires with a drive current in accordance with a gain parameter and a control loop circuit. The control loop circuit is configured to receive a control signal representative of a target current value for the drive current, adjust the gain parameter based on a difference between the target current value and an actual current value of current that is actually being driven through the sensor component, and abstain from adjusting the gain parameter based on current capacitively coupled onto the first and second wires by an external electric field.

Abstract: A neural phantom device configured and arranged to produce a magnetic field to simulate a neural signal. The neural phantom device includes a driver having a signal source configured to produce a simulated neural signal, and either i) a carrier wave source configured to produce a carrier wave having a frequency of at least 250 Hz or ii) an optical carrier wave source configured to produce an optical carrier wave, wherein the driver is configured to modulate the simulated neural signal using the carrier wave or optical carrier wave to generate a modulated signal. The neural phantom device also includes a phantom configured to receive the modulated signal, demodulate the modulated signal to recover the simulated neural signal, and generate the magnetic field in response to the simulated neural signal.

Abstract: Source light having a range of optical wavelengths is generated. The source light is split into sample light and reference light. The sample light is delivered into a sample, such that it is scattered by the sample, resulting in signal light that exits the sample. The signal light and reference light are combined into an interference light pattern having optical modes. Different subsets of the optical modes of the interference light pattern are respectively detected, and high-bandwidth analog signals respectively corresponding to the different subsets of optical modes of the interference light pattern are output. At least one characteristic is extracted from each of the plurality of high-bandwidth analog signals, and low-bandwidth digital signals respectively comprising the extracted characteristics are output. The sample is analyzed based on the low-bandwidth digital signals.

Abstract: An exemplary controller may include a single clock source configured to generate a single clock signal used to drive one or more components within a plurality of magnetometers and a plurality of differential signal measurement circuits configured to measure current output by a photodetector of each of the plurality of magnetometers.

Abstract: An exemplary wearable sensor unit includes 1) a magnetometer comprising a vapor cell comprising an input window and containing an alkali metal, and a light source configured to output light that passes through the input window and into the vapor cell along a transit path, and 2) a temperature control circuit external to the vapor cell and configured to create a temperature gradient within the vapor cell, the temperature gradient configured to concentrate the alkali metal within the vapor cell away from the transit path of the light.

Abstract: The source light having a range of optical wavelengths is split into sample light and reference light. The sample light is delivered into a sample, such that the sample light is scattered by the sample, resulting in signal light that exits the sample. The signal light and the reference light are combined into an interference light pattern having optical modes having oscillation frequency components respectively corresponding to optical pathlengths extending through the sample. Different sets of the optical modes of the interference light pattern are respectively detected, and high-bandwidth analog signals representative of the optical modes of the interference light pattern are output. The high-bandwidth analog signals are parallel processed, and mid-bandwidth digital signals are output. The mid-bandwidth digital signals are processed over an i number of iterations, and a plurality of low-bandwidth digital signals are output on the ith iteration.

Abstract: A neural sensing system includes an interrogator that includes an optical head. The optical head is configured to transmit a light signal. The neural sensing system also includes a microprobe configured to contact tissue. The microprobe includes a transducer configured to receive the light signal and modulate the light signal with neural signal information sensed from the tissue. The microprobe also includes a retroreflector configured to reflect the modulated light signal back to the optical head of the interrogator.

Abstract: An exemplary magnetic field measurement system includes a wearable sensor unit that includes a magnetometer and a twisted pair cable interface assembly electrically connected to the magnetometer.

Abstract: A magnetic field measurement system includes a wearable device having a plurality of wearable sensor units. Each wearable sensor unit includes a plurality of magnetometers and a magnetic field generator configured to generate a compensation magnetic field configured to actively shield the plurality magnetometers from ambient background magnetic fields. A strength of a fringe magnetic field generated by the magnetic field generator of each of the wearable sensor units is less than a predetermined value at the plurality of magnetometers of each wearable sensor unit included in the plurality of wearable sensor units.

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: 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: Source light having a range of optical wavelengths is generated. The source light is split into sample light and reference light. The sample light is delivered into a sample, such that the sample light is scattered by the sample, resulting in signal light that exits the sample. The signal light and the reference light are combined into an interference light pattern having optical modes, each having a direct current (DC) component and at least one alternating current (AC) component. Different subsets of the optical modes of the interference light pattern are respectively detected, and analog signals representative of the optical modes of the interference light pattern are output. Pair of the analog signals are subtracted from each other, and differential analog signals are output. The sample is analyzed based on the differential analog signals.

Abstract: Memristor devices are provided. In an embodiment, a memristor device comprises a top electrode; a bottom electrode; a dielectric material between the top and bottom electrodes; and an ion-implanted conductive region embedded within the dielectric material, the ion-implanted conductive region comprising the dielectric material. The ion-implanted conductive region forms an interface with the dielectric material such that a voltage applied across the top and bottom electrodes causes electrons to cross the interface as they move between the top and bottom electrodes so that the memristor device exhibits memristance.

Abstract: An array of optically pumped magnetometers includes a vapor cell arrangement having a wafer defining one or more cavities and alkali metal atoms disposed in the cavities to provide an alkali metal vapor; an array of light sources, each of the light sources arranged to illuminate a different portion of the one or more cavities of the vapor cell arrangement with light; at least one mirror arranged to reflect the light from the array of light sources after the light passes through the one or more cavities of the vapor cell arrangement; and an array of detectors to receive light reflected by the at least one mirror, wherein each of the detectors is arranged to receive light originating from one of the light sources.

Abstract: An optical measurement system and method are provided. Pump sample light and probe sample light are delivered through into an anatomical structure of a user. The anatomical structure has molecules having a resonant vibrational frequency equal to the difference between a first optical frequency of the pump sample light and a second optical frequency of the probe sample light, whereby a portion of the probe sample light is inelastically scattered by the molecules as signal light encoded with a physiological event occurring in the molecules, and whereby sample light comprising the signal light exits the anatomical structure. Signal light in the exiting sample light is detected, and an electrical signal representative of the signal light is outputted. The electrical signal is analyzed, and based on this analysis, the presence and the depth of the physiological event in the anatomical structure is determined.

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: An optically pumped magnetometer includes a vapor cell; at least one light source configured to produce a pump light beam and a probe light beam; a lens disposed between the at least one light source and the vapor cell; a quarter wave plate disposed between the lens and the vapor cell; a mirror configured to receive the pump light beam and probe light beam after passing through the vapor cell and reflect the pump light beam and probe light beam back through the vapor cell, the quarter wave plate, and the lens; and at least one detector configured to receive the probe light beam reflected by the mirror.

Abstract: A system to couple light to tissue includes a first light source configured to emit first light of a first wavelength lambda ?1 and a second light source configured to emit second light of a second wavelength ?2. The system also includes a retro-modulator configured to receive the first light and the second light. The retro-modulator is configured to modulate the first light of the first wavelength ?1 based at least in part on an intensity of the second light of the second wavelength ?2. The retro-modulator is also configured to reflect the modulated first light for use in generation of a guide-star within the tissue.

Abstract: A system to generate a space-time scattering network includes a computing unit configured to store a space-time scattering network (STSN) algorithm. The computing unit also executes the STSN algorithm to represent scattering of light through a material mathematically as a tensor field at a location. The computing unit also generates a subnet that represents the tensor field at the location. The computing unit also identifies, based on a translation operator, connections between a plurality of subnets, where each of the subnets in the plurality of subnets represents a given tensor field at a given location. The computing unit also forms the STSN based at least in part on the identified connections between the plurality of subnets. The computing unit further uses the STSN to inversely design an optical component or to perform tomography.

Abstract: A magnetic field measurement system can include at least one magnetometer; and a ferrofluid shield disposed at least partially around the at least one magnetometer. For example, the ferrofluid shield can include a microfluid fabric and a ferrofluid disposed in or flowable into the microfluid fabric. As another example, the ferrofluid shield can include a ferrofluid and a controller configured to alter an arrangement of the ferrofluid within the ferrofluid shield.