Systems and methods for a magnetometer comprise a single-isotope silicon crystal doped with impurity atoms. The Larmor precession associated with energy level transitions of the impurity atoms may be detected and used to measure an external magnetic field.

Systems and methods for a magnetometer comprise a single-isotope silicon crystal doped with impurity atoms. The Larmor precession associated with energy level transitions of the impurity atoms may be detected and used to measure an external magnetic field.

A magnetic resonance imaging apparatus according to an embodiment includes an acquiring unit, a detecting unit, a deriving unit, and an imaging controller. The acquiring unit acquires three-dimensional image data including a target organ. The detecting unit detects an upper end position and a lower end position of the target organ in the three-dimensional image data. The deriving unit derives an imaging range of subsequent imaging performed after acquisition of the three-dimensional image data based on the upper end position and the lower end position of the target organ. The imaging controller controls performance of the subsequent imaging in accordance with the imaging range.

A computer-implemented method is disclosed for providing an actuation sequence which specifies transmit signals for at least one high-frequency transmit channel of an antenna arrangement of a magnetic resonance device for acquiring measurement data of an object under investigation by the magnetic resonance device. The method includes providing different actuation sequences, wherein each sequence is the result of an optimization method and which differs with regard to the value of an optimization parameter taken into account in the course of the optimization method. The method further includes providing a plurality of field distribution maps, (e.g., at least one B.sub.0 map and/or at least one B.sub.1 map), acquired by the or a further magnetic resonance device from the object under investigation. The method further includes selecting the actuation sequence to be used from the different actuation sequences depending on the field distribution maps and providing the actuation sequence to be used.

A method of observing axial magnetization (Mz) in an object (O) located in a main magnetic field (B.sub.0) comprises the step of determining magnetic field intensity (B.sub.p) in at least one magnetic field probe (P) arranged in the neighborhood of the object. The magnetic field probe comprises a magnetic resonance (MR) active substance, means for pulsed MR excitation of the substance and means for receiving an MR signal generated by said substance.

A method of observing axial magnetization (Mz) in an object (O) located in a main magnetic field (B.sub.0) comprises the step of determining magnetic field intensity (B.sub.p) in at least one magnetic field probe (P) arranged in the neighborhood of the object. The magnetic field probe comprises a magnetic resonance (MR) active substance, means for pulsed MR excitation of the substance and means for receiving an MR signal generated by said substance.

A system and method for determining a magnetic field map when using a magnetic resonance imaging (MRI) system to acquire images from a region of interest (ROI) of a subject. The method includes selecting a pulse sequence to elicit a plurality of echoes from the subject as medical imaging data from the subject. The method also includes optimizing an echo time for a dynamic range of interest during the pulse sequence (SB.sub.max), a minimum signal-to-noise ratio (SNR.sub.0) in the medical imaging data, and minimum T2* value in the ROI. The method further includes generating a magnetic field map estimation using the optimized echo times.

Systems and methods for magnetic resonance imaging, including adjusting spatial distribution of a rotating magnetic field. By minimizing imaging time, the B.sub.1 nonuniformity reducing effect of RF shimming is maximized for an imaging section of an arbitrary axis direction and an arbitrary position. B.sub.1 distributions are measured for only several sections of one predetermined direction, and a radio frequency magnetic field condition that maximizes the B.sub.1 non-uniformity reducing effect for an imaging section of an arbitrary direction and an arbitrary position is calculated from the B.sub.1 distribution data.

A solid state electronic spin system contains electronic spins disposed within a solid state lattice and coupled to an electronic spin bath and a nuclear spin bath, where the electronic spin bath composed of electronic spin impurities and the nuclear spin bath composed of nuclear spin impurities. The concentration of nuclear spin impurities in the nuclear spin bath is controlled to a value chosen so as to allow the nuclear spin impurities to effect a suppression of spin fluctuations and spin decoherence caused by the electronic spin bath. Sensing devices such as magnetic field detectors can exploit such a spin bath suppression effect, by applying optical radiation to the electronic spins for initialization and readout, and applying RF pulses to dynamically decouple the electronic spins from the electronic spin bath and the nuclear spin bath.

A magnetometer is provided which measures an ambient magnetic field having a frequency range of interest. An optical pumping source emits in the direction of a cell filled with an atomic gas a light beam linearly polarised in a polarisation direction. A parametric resonance excitation circuit induces in the cell a radiofrequency magnetic field having two components orthogonal to the polarisation direction and each oscillating at its own oscillation frequency. A parametric resonance detection circuit performs synchronous detection at an inter-harmonic of oscillation frequencies of an electrical signal outputted by a photodetector arranged to receive the light beam having passed through the cell. A zero-field servo-control circuit generates from the synchronous detection a compensation magnetic field opposite to a component of the ambient magnetic field oriented in the polarisation direction. The servo-control circuit is configured so the compensation magnetic field has an attenuation within the frequency range of interest.