A method for producing a solid composition according to the present disclosure is a method for producing a solid composition that is used for forming a functional ceramic having a first crystal phase. The method for producing a solid composition includes: producing an oxide composed of a second crystal phase different from the first crystal phase; and mixing the oxide and an oxo acid compound.

A device for unidirectional propagation of microwaves comprises a resonant microwave structure arranged to transmit microwaves between two ports and a magnetic source arranged to provide a generally static magnetic field and to have a resonant frequency distinct from that of the microwave structure, which is disposed adjacent the microwave structure so as to be located in presence of electromagnetic fields emanating from the transmitted microwaves such that the magnetic field interacts with the electromagnetic fields of the microwaves so as to form a set of hybridized resonant frequencies at which zero intrinsic damping exists, one of the set of hybridized resonant frequencies being a real eigenvalue providing the unidirectional propagation from one of the first and second ports to the other. A related method comprises arranging the magnetic source at a prescribed position where the real eigenvalue matches the frequency of an input signal applied at a selected port.

Provided is a new magnetic material with high magnetic stability, as well as a manufacturing method therefor, said magnetic material having a higher saturation magnetization than ferrite-based magnetic materials, and having a higher electrical resistivity than existing metal-based magnetic materials, thus solving problems such as that of eddy current loss. Ti-ferrite nanoparticles obtained through wet synthesis are reduced within hydrogen, and grains are allowed to grow while simultaneously using a phase separation phenomenon due to a disproportionation reaction to produce a magnetic material powder in which an α-(Fe, Ti) phase and a Ti-enriched phase are nano-dispersed. This powder is then sintered to produce a solid magnetic material.

A production method for a magnetic material, which is expressed by a chemical structure formula Fe(Al.sub.1-xMn.sub.x).sub.2O.sub.4, where 0<x<1, and exhibits ferromagnetism, includes: preparing a mixed aqueous solution by dissolving, in distilled water, Fe nitrate, Al nitrate, and an oxide including Mn, the Fe nitrate, the Al nitrate, and the oxide being parent materials; preparing a metal-citric acid complex by mixing citric acid and ethylene glycol with the mixed aqueous solution; obtaining a precursor by boiling the metal-citric acid complex to a gel and drying the gel; and obtaining the magnetic material by sintering the precursor.

Disclosed herein is a nonreciprocal circuit element that includes a magnetic rotator disposed between first and second ground conductors, and a permanent magnet that applies a DC magnetic field to the magnetic rotator. The magnetic rotator includes a first ferrite core having a first surface covered with the first ground conductor, a second ferrite core having a second surface covered with the second ground conductor, a first center conductor directly fixed to a third surface of the first ferrite core positioned opposite to the first surface, and a second center conductor directly fixed to a fourth surface of the second ferrite core positioned opposite to the second surface.

A ferrite composition includes main-phase particles, first sub-phase particles, second sub-phase particles, and a grain boundary. At least 10% or more of the main-phase particles contain a portion whose Zn concentrations monotonously decrease from a particle surface toward a particle central part along a length of 50 nm or more. The first sub-phase particles contain Zn.sub.2SiO.sub.4. The second sub-phase particles contain SiO.sub.2. A total area ratio of the first sub-phase particles and the second sub-phase particles is 30.5% or more.

Disclosed are methods of forming a single-piece magnetically tunable ferrite rods that can be used for radio-frequency (RF) applications, including using synthetic garnets. This can include methods of forming cellular towers and antennas. In some embodiments, a separate tuner need not be used in the resonator during magnetic tuning. Examples of fabrication methods and RF-related properties are disclosed.

Disclosed herein are ceramic materials, such as bismuth substituted garnets, which can have high curie temperatures and high dielectric constants. In certain implementations, indium can be incorporated into the ceramic to improve certain properties and to avoid calcium compensation. The ceramic materials disclosed herein can be particular advantageous for below resonance applications.

Disclosed herein are embodiments of low temperature co-fireable dielectric materials which can be used in conjunction with high dielectric materials to form composite structures, in particular for isolators and circulators for radiofrequency components. Embodiments of the low temperature co-fireable dielectric materials can be scheelite or garnet structures, for example, bismuth vanadate. Adhesives and/or glue is not necessary for the formation of the isolators and circulators.

A method of forming a composite material for use as an isolator or circulator in a radiofrequency device comprises providing a low temperature fireable outer material, the low fireable outer material having a garnet or scheelite structure, inserting a high dielectric constant inner material having a dielectric constant above 30 within an aperture in the low temperature fireable outer material, and co-firing the lower temperature fireable outer material and the high dielectric constant inner material together at temperature between 650-900? C. to shrink the low temperature fireable outer material around an outer surface of the high dielectric constant inner material to form an integrated magnetic/dielectric assembly without the use of adhesive or glue.