Abstract: A magnetic field gradiometer for determining a magnetic field gradient includes at least one excitation light source for emitting excitation light, and two spatially spaced-apart measuring areas for magnetic field measurement. Color centers in diamond are arranged in the two measuring areas. The color centers emit fluorescent light upon excitation using the excitation light. The magnetic field gradiometer further includes at least one microwave emitter for applying at least one microwave field to the spatially spaced-apart measuring areas, two detectors for detecting the fluorescent light from the two spatially spaced-apart measuring areas, and an evaluator for determining the magnetic field gradient based on the fluorescent light detected by the two detectors. The two measuring areas are configured as freestanding measuring waveguides of a common diamond crystal. The diamond crystal is used as a substrate for the measuring waveguides.

Abstract: A method for determining the vital functions of a vehicle occupant enables precise measurements and is easy to use without negatively affecting the vehicle occupant. The method includes determining the vital functions of the vehicle occupant using a sensor device integrated in a vehicle seat of a motor vehicle, and acquiring measurement signals of the vehicle occupant from which cardiogram signals are acquired. The method further includes using an evaluation unit to ascertain the vital functions of the vehicle occupant from the cardiogram signals. The sensor device is a magnetic field sensor device, and the cardiogram signals are magnetic cardiogram signals.

Abstract: A method for determining an external magnetic field with an NV magnetometer includes recording single resonance signals for determining resonance frequencies by using frequency-modulated microwave radiation emitted onto a sensor material in frequency bands based on a microwave frequency and a carrier frequency, recording a double resonance signal with a dispersive form and a linear range around the resonance frequencies, determining a slope of the linear range as a scalar factor from the double resonance signal, observing a detuning of the resonance frequencies via the double resonance signal with resonant emission of the microwave radiation due to external magnetic field changes, controlling the frequency bands based on the observed detuning so that the frequency bands remain in the range of the resonance frequencies present at the detuning even after the detuning has occurred, and determining the external magnetic field from a distance of the frequency bands and the detuning ?B.

Abstract: A sensor unit for detecting brain current-induced magnetic fields in an unshielded environment has a plurality of gradiometer units configured for arrangement around a head of a user. Each gradiometer unit has two magnetometers which are arranged at a fixed distance from each other. Each magnetometer has a sensor medium and is configured to detect a magnetic field strength at a measurement location by reading a spin resonance in the sensor medium depending on the magnetic field strength. The sensor unit further includes at least one excitation light source for radiating light into the sensor media of the magnetometer. The sensor unit further incudes at least one signal processing unit for determining a magnetic field gradient at a gradiometer unit as a difference of the output signals of the two magnetometers of the gradiometer unit and for detecting a time course of the magnetic field gradient.

Abstract: A method for determining an external magnetic field with an NV magnetometer includes recording single resonance signals for determining resonance frequencies by using frequency-modulated microwave radiation emitted onto a sensor material in frequency bands based on a microwave frequency and a carrier frequency, recording a double resonance signal with a dispersive form and a linear range around the resonance frequencies, determining a slope of the linear range as a scalar factor from the double resonance signal, observing a detuning of the resonance frequencies via the double resonance signal with resonant emission of the microwave radiation due to external magnetic field changes, controlling the frequency bands based on the observed detuning so that the frequency bands remain in the range of the resonance frequencies present at the detuning even after the detuning has occurred, and determining the external magnetic field from a distance of the frequency bands and the detuning ?B.

Abstract: A method for measuring a magnetic field includes radiating a microwave field having a first frequency into at least one measuring location in a crystal, which comprises optically excitable color center defects at the measuring location, radiating excitation light and detecting resulting fluorescence light, applying a deformation force which results in local mechanical strain, wherein an applied first deformation force is selected such that the first frequency corresponds to a resonance frequency of the color center defects under the action of the first deformation force without the magnetic field to be measured and the detected fluorescence light becomes minimal. The method further includes placing the sensor into the magnetic field to be measured to bring about a shift in the resonance frequency and varying the applied deformation force to compensate the shift in the resonance frequency until a minimum fluorescence signal is again acquired at a second deformation force.

Abstract: A method is for measuring phase currents of a device under test, in particular of an inverter, in which a sensor arrangement, which has a component including a crystal lattice with a defect, is arranged in a region of the device under test. The method includes using the sensor arrangement to detect a magnetic field formed by a vector of magnetic fields, the magnetic fields each in turn being brought about by one of the phase currents of the device under test, and calculating a vector of the phase currents from the vector of the magnetic fields based on a coefficient matrix.

Abstract: A method for determining the vital functions of a vehicle occupant enables precise measurements and is easy to use without negatively affecting the vehicle occupant. The method includes determining the vital functions of the vehicle occupant using a sensor device integrated in a vehicle seat of a motor vehicle, and acquiring measurement signals of the vehicle occupant from which cardiogram signals are acquired. The method further includes using an evaluation unit to ascertain the vital functions of the vehicle occupant from the cardiogram signals. The sensor device is a magnetic field sensor device, and the cardiogram signals are magnetic cardiogram signals.

Abstract: A method for determining a rotational orientation change using an NMR gyroscope includes making use of a measure of determining, in a vapor cell, which is filled at least with a gaseous first element and a gaseous second element having non-vanishing nuclear spin, a nuclear spin component of the second element in the second direction and a nuclear spin component of the second element in a third direction. The second direction and the third direction are perpendicular to a first direction, which corresponds to the direction of the static magnetic field and to the polarization direction of the nuclear spin of the second element. Moreover, the second direction corresponds to the direction of an applied alternating magnetic field, the frequency of which corresponds to the Larmor frequency of the Larmor precession of the nuclear spin of the second element about the static magnetic field.

Abstract: A magnetic field gradiometer for determining a magnetic field gradient includes at least one excitation light source for emitting excitation light, and two spatially spaced-apart measuring areas for magnetic field measurement. Color centers in diamond are arranged in the two measuring areas. The color centers emit fluorescent light upon excitation using the excitation light. The magnetic field gradiometer further includes at least one microwave emitter for applying at least one microwave field to the spatially spaced-apart measuring areas, two detectors for detecting the fluorescent light from the two spatially spaced-apart measuring areas, and an evaluator for determining the magnetic field gradient based on the fluorescent light detected by the two detectors. The two measuring areas are configured as freestanding measuring waveguides of a common diamond crystal. The diamond crystal is used as a substrate for the measuring waveguides.

Abstract: A magnetic field gradiometer for determining a magnetic field gradient includes at least one excitation light source for emitting excitation light, and two spatially spaced-apart measuring areas for magnetic field measurement. Color centers in diamond are arranged in the two measuring areas. The color centers emit fluorescent light upon excitation using the excitation light. The magnetic field gradiometer further includes at least one microwave emitter for applying at least one microwave field to the spatially spaced-apart measuring areas, two detectors for detecting the fluorescent light from the two spatially spaced-apart measuring areas, and an evaluator for determining the magnetic field gradient based on the fluorescent light detected by the two detectors. The two measuring areas are configured as freestanding measuring waveguides of a common diamond crystal. The diamond crystal is used as a substrate for the measuring waveguides.

Abstract: A method for measuring a magnetic field includes radiating a microwave field having a first frequency into at least one measuring location in a crystal, which comprises optically excitable color center defects at the measuring location, radiating excitation light and detecting resulting fluorescence light, applying a deformation force which results in local mechanical strain, wherein an applied first deformation force is selected such that the first frequency corresponds to a resonance frequency of the color center defects under the action of the first deformation force without the magnetic field to be measured and the detected fluorescence light becomes minimal. The method further includes placing the sensor into the magnetic field to be measured to bring about a shift in the resonance frequency and varying the applied deformation force to compensate the shift in the resonance frequency until a minimum fluorescence signal is again acquired at a second deformation force.

Abstract: A method is for measuring phase currents of a device under test, in particular of an inverter, in which a sensor arrangement, which has a component including a crystal lattice with a defect, is arranged in a region of the device under test. The method includes using the sensor arrangement to detect a magnetic field formed by a vector of magnetic fields, the magnetic fields each in turn being brought about by one of the phase currents of the device under test, and calculating a vector of the phase currents from the vector of the magnetic fields based on a coefficient matrix.

Abstract: A method of sequencing a prepared DNA strand includes providing the prepared DNA strand with nucleotides of the types dATP, dCTP, dGTP and/or dTTP, wherein at least one of the types of the nucleotides comprises a predetermined magnetic label. The method further includes placing the prepared DNA strand within a measuring range of a sensor unit comprising an operatively connected magneto-optical transducer unit and an optical sensor and optically exciting the magneto-optical transducer unit. The method continues with acquiring at least one value indicative of a fluorescence signal of the magneto-optical transducer unit, and assigning the acquired value to the at least one type of the nucleotides comprising the predetermined magnetic label.

Abstract: A method for determining a rotational orientation change using an NMR gyroscope includes making use of a measure of determining, in a vapor cell, which is filled at least with a gaseous first element and a gaseous second element having non-vanishing nuclear spin, a nuclear spin component of the second element in the second direction and a nuclear spin component of the second element in a third direction. The second direction and the third direction are perpendicular to a first direction, which corresponds to the direction of the static magnetic field and to the polarization direction of the nuclear spin of the second element. Moreover, the second direction corresponds to the direction of an applied alternating magnetic field, the frequency of which corresponds to the Larmor frequency of the Larmor precession of the nuclear spin of the second element about the static magnetic field.

Abstract: A method for forming at least one freestanding microstructure on a diamond crystal includes the step of removing material from the diamond crystal so as to form a structured surface, wherein the removing of the material includes creating at least two trenches, each trench having a bottom and two side walls and wherein adjacent side walls of the at least two trenches form side walls of the structured surface. The method also includes the steps of depositing at least one masking layer on the structured surface, removing at least a portion of the at least one masking layer from the bottom of each of the at least two trenches, removing additional material from the diamond crystal at least along the side walls so as to deepen the trenches, and undercutting the diamond crystal so as to form the freestanding microstructure.

Abstract: A method for ascertaining a change in a spatial orientation of a nuclear magnetic resonance (NMR) gyroscope having a diamond doped with color centers includes applying a static external magnetic field in a first direction, polarizing a nuclear spin of the color centers of the diamond in a direction of the static magnetic field, and generating a cophasal Larmor precession of the nuclear spin of the color centers of the diamond through application of an alternating magnetic field in a second direction perpendicular to the first direction, whose frequency corresponds to the Larmor frequency of the nuclear spin of the color centers. The method further includes measuring a phase of the Larmor precession, and ascertaining a change in the spatial orientation in a plane perpendicular to the first direction based on a deviation of the precession frequency from an expected value.

Abstract: A method for ascertaining a change in a spatial orientation of a nuclear magnetic resonance (NMR) gyroscope having a diamond doped with color centers includes applying a static external magnetic field in a first direction, polarizing a nuclear spin of the color centers of the diamond in a direction of the static magnetic field, and generating a cophasal Larmor precession of the nuclear spin of the color centers of the diamond through application of an alternating magnetic field in a second direction perpendicular to the first direction, whose frequency corresponds to the Larmor frequency of the nuclear spin of the color centers. The method further includes measuring a phase of the Larmor precession, and ascertaining a change in the spatial orientation in a plane perpendicular to the first direction based on a deviation of the precession frequency from an expected value.

Abstract: A production method for a layer structure, including providing a substrate, wherein at least a top surface of the substrate is made from a non-conductive material; depositing a catalyst structure onto the top surface of the substrate; depositing a graphene structure onto the catalyst structure; and at least partially removing the catalyst structure situated between the substrate and the graphene structure.

Abstract: A device for analyzing substances in a sample on the basis of a measurement of nuclear magnetic resonances including a magnetic field device configured to generate a magnetic field. The device is configured such that, in order to detect magnetic resonances induced in the sample by the generation of the magnetic field, provision is made of at least one magnetic field sensor which comprises at least one sensitive component with diamond structures. The diamond structures have nitrogen vacancy centers.