Abstract: A patterned nonreciprocal optical resonator structure is provided that includes a resonator structure that receives an optical signal. A top cladding layer is deposited on a selective portion of the resonator structure. The top cladding layer is patterned so as to expose the core of the resonator structure defined by the selective portion. A magneto-optically active layer includes a magneto-optical medium being deposited on the exposed core of the resonator structure so as to generate optical non-reciprocity.

Abstract: A patterned nonreciprocal optical resonator structure is provided that includes a resonator structure that receives an optical signal. A top cladding layer is deposited on a selective portion of the resonator structure. The top cladding layer is patterned so as to expose the core of the resonator structure defined by the selective portion. A magneto-optically active layer includes a magneto-optical medium being deposited on the exposed core of the resonator structure so as to generate optical non-reciprocity.

Abstract: A magneto-optical structure is provided. The magneto-optical structure includes a substrate. A waveguide layer is formed on the substrate for guiding electromagnetic radiation received by the magneto-optical structure. The waveguide layer includes magnetic oxide material that comprises ABO3 perovskite doped with transition metal ions on the B site, or transition metal ions doped SnO2, or transition metal ions doped CeO2.

Abstract: A magneto-optical isolator device is provided. The isolator device includes a substrate and a bottom cladding layer that is formed on the substrate. An optical resonator structure is formed on the bottom cladding layer. The resonator structure includes crystalline or amorphous diamagnetic silicon or silicon-germanium so as to provide non-reciprocal optical isolation. A top cladding layer is formed on the resonator structure. One or more magnetic layers positioned on the top cladding layer or between the top cladding or bottom cladding layers and the optical resonator structure.

Abstract: A magneto-optical structure is provided. The magneto-optical structure includes a substrate. A waveguide layer is formed on the substrate for guiding electromagnetic radiation received by the magneto-optical structure. The waveguide layer includes magnetic oxide material that comprises ABO3 perovskite doped with transition metal ions on the B site, or transition metal ions doped SnO2, or transition metal ions doped CeO2.

Abstract: A method for improving the magnetic resonance imaging contrast of a selected portion of a sample. A selected ferrimagnetic constituent is associated with the sample portion, by molecular or biological attachment or by some other means, so that the sample portion is distinguished from other adjacent portions of the sample that do not have the selected ferrimagnetic constituent associated therewith. Alternatively, the sample portion is suspected, but not yet confirmed, to have the selected ferrimagnetic constituent associated with it. Ferromagnetic resonance imaging is performed on the sample portion, and at least one resonance frequency ?0 of the sample portion is provided. At least one material parameter of the sample portion is measured at or near the frequency ?0, with enhanced imaging contrast relative to adjacent portions of the sample that do not have the selected ferrimagnetic constituent in association.

Abstract: A device responsive to an electromagnetic signal includes a conductor for conducting the electromagnetic signal, a magnetic structure disposed proximate the conductor to enable gyromagnetic interaction between the electromagnetic signal and the magnetic structure and a transducer disposed on the magnetic structure for controlling a domain pattern in the magnetic structure.

Abstract: Passive solid-state magnetic sensors are based on the combination of magnetorestrictive materials and piezoelectric materials. Sensors have applications in rotor speed detection, magnetic field detection, read heads, and MRAM, for example.

Abstract: Passive solid-state magnetic sensors comprise a magnetostrictive material in contact with a piezoelectric material. The magnetostrictive material strains under the influence of an external magnetic field and imparts stress to the piezoelectric material to produce a detectable voltage signal indicative of the external field. Sensors have applications in rotor speed detection, electrical current measurements, magnetic imaging, magnetic field detection, read heads, and MRAM, for example.

Abstract: Methods for spatially resolve spin resonance detection in a sample of material, with a resolution as small as 0.5 &mgr;m-1 mm. In one embodiment, a coupler having at least one pair of degenerate orthogonal modes provides an evanescent input signal along one coupler axis to the sample, to which a magnetic field is applied, and senses a spin interaction signal along another coupler axis. In another embodiment, an evanescent input signal is applied to the sample along one of two identical transmission line resonators, and a difference of the two resonator signals provides a spin interaction signal. In another embodiment, a polarized laser beam provides an evanescent input signal to the sample, and the spin interaction signal is sensed according to a second beam polarization direction. Certain ferromagnetic or ferrimagnetic molecules, such as YIG, can be used to tag selected chemical and biological molecules, using spatially resolved spin resonance detection for interrogation.

Abstract: A device responsive to an electromagnetic signal includes a conductor for conducting the electromagnetic signal, a magnetic structure disposed proximate the conductor to enable gyromagnetic interaction between the electromagnetic signal and the magnetic structure and a transducer disposed on the magnetic structure for controlling a domain pattern in the magnetic structure.

Abstract: Passive solid-state magnetic sensors are based on the combination of magnetorestrictive materials and piezoelectric materials. Sensors have applications in motor speed detection, magnetic field detection, read heads, and MRAM, for example.

Abstract: Passive solid-state magnetic sensors are based on the combination of magnetorestrictive materials and piezoelectric materials. Sensors have applications in rotor speed detection, magnetic field detection, read heads, and MRAM, for example.

Abstract: Passive solid-state magnetic sensors are based on the combination of magnetorestrictive materials and piezoelectric materials. Sensors have applications in rotor speed detection, magnetic field detection, read heads, and MRAM, for example.

Abstract: In a ferrite switchable microwave device, a magnetic structure is formed in a nearly continuous closed-loop configuration of a single crystal material, or of a material exhibiting the magnetic properties of single crystal materials (quasi-single crystal materials). A magnetization M is induced in the structure. The toroidal shape of the structure in combination with the properties of the magnetic material results in a device which exhibits virtually no hysteresis. The device is operable either in a fully magnetized state or in a partially magnetized state. In a fully magnetized state, the device operates in the region of magnetic saturation. The absence of hysteresis in the device enables switching between the positive and negative magnetic saturation points with very little energy. In a partially magnetized state, the device provides a variable magnetization M between the two saturation points.

Abstract: In a magnetically-tunable resonator, a wave-guiding structure comprising an electromagnetic frequency filter, or component of such a filter, is placed in sufficient proximity with a magnetic structure so as to be gyromagnetically coupled therewith. The resonator is supportable of two fundamental normal modes of propagation which, in the absence of magnetic interaction are even and odd with respect to the resonator center plane of symmetry. Each normal mode possesses a spectrum of resonance frequencies. When the magnetic structure is magnetized, the formerly even and odd modes become mixed due to gyromagnetic interaction, and the resulting wave fields become elliptically polarized. With appropriate design such that the identities of the modes are preserved under conditions of resonance, this in turn results in a nonreciprocal reinforcement action in the resonator, which leads to the desired shift in resonance frequency in at least one of the two normal modes.

Abstract: In an apparatus and method for forming an advanced ring-network circulator, a plurality of junctions are interconnected by a plurality of non-reciprocal phase shifters. Each junction has a predetermined inductive reactance and capacitive susceptance which renders each junction partially reflective of an incident signal in a predetermined frequency-dependent manner. The junctions are selected such that a predetermined combination of average phase shift and differential phase shift provided between junctions produces substantially ideal circulation about a designated band center, the band center being determined by the selected reactance and susceptance of the junctions. The phase shifters are selected to provide an ideal combination of average phase shift and differential phase shift for providing substantially ideal circulation within a frequency band about the band center in a predetermined frequency dependent manner.

Abstract: An apparatus and method are described for gyromagnetic interaction between the electromagnetic field generated by an electromagnetic signal conducted by a superconductor and the magnetization contained in a magnetic structure. A ferrite magnetic structure is disposed in close proximity to a superconductor conducting the electromagnetic signal. A magnetization is induced in the magnetic structure with a geometry such that the magnetic flux is confined within the magnetic structure or eliminated from the magnetic structure so as not to produce an external magnetic field to interfere with the superconducting properties of the superconductor. The electromagnetic field of the signal conducted by the superconductor interacts gyromagnetically with the magnetization of the magnetic structure, inducing a phase shift in the electromagnetic signal traversing the superconductor. Thus, the invention induces a phase shift in the signal with minimum insertion loss due to electrical resistance.