An apparatus for measuring a magnetic field strength is provided. The apparatus includes a stage on which a sample to be measured is placed, a cantilever having a tip, an optical system having a light source and a light receiver, and a microwave power source. The tip is a diamond tip having a nitrogen vacancy defect. The optical system is configured such that excitation light from the light source is focused at the diamond tip. The cantilever is configured as a coaxial microwave antenna through which microwaves from the microwave power source are supplied to the diamond tip.

A magnetic resonance force detection apparatus, comprising: a sample carrier for carrying a sample to be tested; a magnetic field source configured to provide a magnetic field to a sample when it is carried by the sample carrier; a support for supporting either the sample carrier or the magnetic field source; a support-driving-mechanism configured to drive the support such that the sample carrier moves relative to the magnetic field source, such that the magnetic field is configured to cause the spins of one or more nuclei or electrons in the sample to flip, and wherein the flipping of spins exerts a force on the support; and a support-displacement-measuring-sensor configured to measure displacement of the support and generate a signal representative of the displacement of the support.

A magnetic resonance force detection apparatus, comprising: a sample carrier for carrying a sample to be tested; a magnetic field source configured to provide a magnetic field to a sample when it is carried by the sample carrier; a support for supporting either the sample carrier or the magnetic field source; a support-driving-mechanism configured to drive the support such that the sample carrier moves relative to the magnetic field source, such that the magnetic field is configured to cause the spins of one or more nuclei or electrons in the sample to flip, and wherein the flipping of spins exerts a force on the support; and a support-displacement-measuring-sensor configured to measure displacement of the support and generate a signal representative of the displacement of the support.

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 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.

An MRI pulse sequence is disclosed. The pulse sequence involves a plurality of slice selective pulses (51,55) which each individually have a desired rotation that is less than or equal to the total desired rotation. The slice selective pulses each cause a rotation about respective axes, which may be different to each other. Optionally phase correction (re-phasing) gradients (53, 56) can also be included in the pulse sequence.

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 metrology device for determining metrological characteristics of a sample is described that includes a probe, a scanning mechanism, a radiation source, an optical sensor and a signal processor. In operation the scanning mechanism displaces the probe relative to the sample, along a surface of the sample. The probe has a diamond tip with one or more nitrogen-vacancy centers and is irradiated by the radiation source with photon radiation to excite the diamond tip to emit fluorescent light. The optical sensor provides a sense signal indicative of an intensity of the emitted fluorescent light and the signal processor processes the sense signal to compute at least one characteristic of a feature present in the sample.

A method for performing sub-nanometer three-dimensional magnetic resonance imaging of a sample under ambient conditions using a diamond having at least one shallowly planted nitrogen-vacancy (NV) center. A driving radio-frequency (RF) signal and a microwave signal are applied to provide independent control of the NV spin and the target dark spins. A magnetic-field gradient is applied to the sample with a scanning magnetic tip to provide a narrow spatial volume in which the target dark electronic spins are on resonance with the driving RF field. The sample is controllably scanned by moving the magnetic tip to systematically bring non-resonant target dark spins into resonance with RF signal. The dark spins are measured and mapped by detecting magnetic resonance of said nitrogen-vacancy center at each of said different magnetic tip positions. The dark-spin point-spread-function for imaging the dark spins is directly measured by the NV center.

A method for performing sub-nanometer three-dimensional magnetic resonance imaging of a sample under ambient conditions using a diamond having at least one shallowly planted nitrogen-vacancy (NV) center. A driving radio-frequency (RF) signal and a microwave signal are applied to provide independent control of the NV spin and the target dark spins. A magnetic-field gradient is applied to the sample with a scanning magnetic tip to provide a narrow spatial volume in which the target dark electronic spins are on resonance with the driving RF field. The sample is controllably scanned by moving the magnetic tip to systematically bring non-resonant target dark spins into resonance with RF signal. The dark spins are measured and mapped by detecting magnetic resonance of said nitrogen-vacancy center at each of said different magnetic tip positions. The dark-spin point-spread-function for imaging the dark spins is directly measured by the NV center.