An apparatus comprises a first substrate and two coils supported by the first substrate and arranged next to each other, the coils configured to each generate a magnetic field which produces eddy currents in and a reflected magnetic field from a conductive target, the two coils arranged so their respectively generated magnetic fields substantially cancel each other in an area between the coils. One or more magnetic field sensing elements are positioned in the area between the coils and configured to detect the reflected magnetic field.

An object wave made of an electron beam influenced by a sample and reference beam made of an electron beam not influenced by the sample are made to interfere with each other where a magnetic field has been applied to the sample to create a first electron-beam hologram and create a first reconstructed phase image from the first electron-beam hologram. An object wave made of an electron beam influenced by the sample and a reference beam made of an electron beam not influenced by the sample are made to interfere where a magnetic field has not been applied to the sample to create a second electron-beam hologram and create a second reconstructed phase image from the second electron-beam hologram. Magnetic field information indicating the influence of the magnetic field on the sample is acquired on the basis of the difference between the first and second reconstructed phase images.

Microwave resonator readout of the cavity-spin interaction between a spin defect center ensemble and a microwave resonator yields fidelities that are orders of magnitude higher than is possible with optical readouts. In microwave resonator readout, microwave photons probe a microwave resonator coupled to a spin defect center ensemble subjected to a physical parameter to be measured. The physical parameter shifts the spin defect centers' resonances, which in turn change the dispersion and/or absorption of the microwave resonator. The microwave photons probe these dispersion and/or absorption changes, yielding a measurement with higher visibility, lower shot noise, better sensitivity, and higher signal-to-noise ratio than a comparable fluorescence measurement. In addition, microwave resonator readout enables coherent averaging of spin defect center ensembles and is compatible with spin systems other than nitrogen vacancies in diamond.

A high-frequency magnetic field generating device includes two coils arranged with a predetermined gap in parallel with each other, the two coils (a) in between which electron spin resonance material is arranged or (b) arranged at one side from electron spin resonance material; a high-frequency power supply that generates microwave current that flows in the two coils; and a transmission line part connected to the two coils, that sets a current distribution so as to locate the two coils at positions other than a node of a stationary wave.

Applying a bias magnetic field to a solid-state spin sensor enables vector magnetic field measurements with the solid-state spin sensor. Unfortunately, if the bias magnetic field drifts slowly, it creates noise that confounds low-frequency field measurements. Fortunately, the undesired slow drift of the magnitude of the bias magnetic field can be removed, nullified, or cancelled by reversing the direction (polarity) of the bias magnetic field at known intervals. This makes the resulting solid-state spin sensor system suitable for detecting low-frequency (mHz, for example) changes in magnetic field or other physical parameters.

A sensing device comprises a plurality of magnetoresistive (MR) sensors, at least one fluidic channel, and detection circuitry coupled to the MR sensors. Each MR sensor is configured to detect the presence of molecules (e.g., biologic molecules) labeled by magnetic nanoparticles (MNPs). The sensors are encapsulated by an insulating material that protects the sensors from the contents of the at least one fluidic channel. The insulating material has a surface within the fluidic channel that provides sites for binding the molecules to be detected. The detection circuitry is configured to detect (a) a characteristic of magnetic noise of each MR sensor, the characteristic being influenced by a presence or absence of one or more MNPs at each site, or (b) a change in resistance, current, and/or voltage drop of each MR sensor, wherein the change is influenced by the presence or absence of one or more MNPs at each site.

The invention generally concerns an enhanced process for detecting spin states of nitrogen vacancy centers in diamonds.

Voltage-controlled spin field effect transistors (“spin transistors”) and methods for their use in switching applications are provided. In the spin transistors, spin current is transported from a spin injection contact to a spin detection contact through a multiferroic antiferromagnetic channel via magnon propagation. The spin current transport is modulated by the application of a gate voltage that increases the number of domain boundaries the multiferroic antiferromagnetic material.

A stacked structure is positioned on a nonmagnetic metal layer. The stacked structure includes a ferromagnetic layer and an intermediate layer interposed between the nonmagnetic metal layer and the ferromagnetic layer. The intermediate layer includes a NiAlX alloy layer represented by Formula (1): Ni.sub.γ1Al.sub.γ2X.sub.γ3 . . . (1), [X indicates one or more elements selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and satisfies an expression of 0<γ<0.5 in a case of γ=γ3/(γ1+γ2+γ3)].

A sensor device includes a carrier, a force feedback sensor, and a probe containing a spin defect, the probe being connected to the force feedback sensor either directly or indirectly via a handle structure. In order to couple the spin defect to a microwave field in an efficient and robust manner, the sensor device includes an integrated microwave antenna arranged at a distance of less than 500 micrometers from the spin defect. The sensor device can be configured as a self-contained exchangeable cartridge that can easily be mounted in a sensor mount of a scanning probe microscope.