60results about "Low dimensional magnetism materials" patented technology

A direct-write method and apparatus for depositing a functional material with a preferred orientation onto a target surface. The method comprises the following steps: (1) forming a precursor fluid to the functional material, with the fluid containing a liquid component; (2) operating a dispensing device to discharge and deposit the precursor fluid onto the target surface in a substantially point-by-point manner and at least partially removing the liquid component from the deposited fluid to form a thin layer of the functional material which is substantially solidified and is of a predetermined pattern; and (3) during the liquid-removing step, subjecting the deposited fluid to a highly localized electric or magnetic field for poling until a preferred orientation is attained in the deposited functional material. The invention also provides a freeform fabrication method for building a multi-layer device, such as a micro-electro-mechanical system (MEMS), which contains sensor and actuator elements that exhibits piezoelectric, pyroelectric, ferromagnetic, electro-optic and / or other functional properties.

The self-assembly of a close-packed, highly-ordered monolayers of molecularly protected nanoparticles on an assembly surface is disclosed. Also disclosed is the transfer of a nanoparticle monolayer from an assembly surface to a transfer surface. The transfer of a monolayer or multilayer structure of nanoparticles from a transfer surface to a substrate by conformal contact of the transfer surface with the substrate is disclosed. Also disclosed is the removal of protective molecules from nanoparticle cores by exposure to an oxidizing atmosphere (optionally in the presence of UV radiation). The exchange of protective molecules in molecularly protected nanoparticles with other molecules is also disclosed.

A process of forming a hard-soft phase, exchange-coupled, magnetic nanocomposite includes forming a dispersion of magnetic nanoparticles, separating the magnetic nanoparticles from a solvent of the dispersion so as to allow self-assembly of the magnetic nanoparticles, and removing a coating from the nanoparticles, which are disposed in a self-assembled, locally-ordered nanostructure.

A method and resultant device, in which metal nanoparticles are self-assembled into two-dimensional lattices. A periodic hole pattern (wells) is fabricated on a photoresist substrate, the wells having an aspect ratio of less than 0.37. The nanoparticles are synthesized within inverse micelles of a polymer, preferably a block copolymer, and are self-assembled onto the photoresist nanopatterns. The nanoparticles are selectively positioned in the holes due to the capillary forces related to the pattern geometry, with a controllable number of particles per lattice point.

A method and apparatus for microencapsulating or electrodeposited coating of ferromagnetic and soft-magnetic sub-micron or nano sized powderized material comprising use of a rotary flow-through device assisted by an electromagnet within the electrode ring to alternately position the powder at the face of the cathode ring and electroplate the powder and reorient it prior to another repositioning. The invention is also of a process and apparatus for forming a strip, mesh, or film from magnetic powderized material in an organized bipolar arrangement, which is particularly useful for electroforming foils with the magnetic particles positioned in a monolayer within a multilayer metallic foil.

An acoustic wave sensor to detect an analyte, the sensor comprising a piezoelectric material including a wide bandgap semiconductor material grown using plasma source molecular beam epitaxy.

A synthetic method of fabricating highly crystalline and monodisperse nanoparticles of metals, multi-metallic alloys, monometallic oxides and multi-metallic oxides without a size selection process are disclosed. A typical synthetic method comprises the steps of, synthesis of a metal surfactant complex from the reaction of a metal precursor and a surfactant, high temperature thermal decomposition of the metal surfactant complex to produce monodisperse metal nanoparticles, and completing the formation of synthesized metal, metal alloy or metal oxide nanoparticles by adding a poor solvent followed by centrifuging. For obtaining highly crystalline monodisperse nanoparticles, additional steps are necessary as described in the invention. The resulting nanoparticles have excellent magnetic property for many applications.

A method and system for magnetic recording using self-organized magnetic nanoparticles is disclosed. The method may include depositing surfactant coated nanoparticles on a substrate, wherein the surfactant coated nanoparticles represent first bits of recorded information. The surfactant coating is then removed from selected of the surfactant coated nanoparticles. The selected nanoparticles with their surfactant coating removed may then be designated to represent second bits of recorded information. The surfactant coated nanoparticles have a first saturation magnetic moment and the selected nanoparticles with the surfactant coating removed have a second saturation magnetic moment. Therefore, by selectively removing the surfactant coating from certain nanoparticles, a write operation for recording the first and second bits of information may be performed. A read operation may be carried out by detecting the different magnetic moments of the surfactant coated nanoparticles and the non-surfactant coated nanoparticles.

A method and resultant device, in which metal nanoparticles are self-assembled into two-dimensional lattices. A periodic hole pattern (wells) is fabricated on a photoresist substrate, the wells having an aspect ratio of less than 0.37. The nanoparticles are synthesized within inverse micelles of a polymer, preferably a block copolymer, and are self-assembled onto the photoresist nanopatterns. The nanoparticles are selectively positioned in the holes due to the capillary forces related to the pattern geometry, with a controllable number of particles per lattice point.

A method and apparatus for microencapsulating or electrodeposited coating of ferromagnetic and soft-magnetic sub-micron or nano sized powderized material comprising use of a rotary flow-through device assisted by an electromagnet within the electrode ring to alternately position the powder at the face of the cathode ring and electroplate the powder and reorient it prior to another repositioning. The invention is also of a process and apparatus for forming a strip, mesh, or film from magnetic powderized material in an organized bipolar arrangement, which is particularly useful for electroforming foils with the magnetic particles positioned in a monolayer within a multilayer metallic foil.

A magnetic body composed of non-magnetic material, includes a plurality of localized electron regions in each of which at least one electron is confined to form a localized spin, a barrier potential region having a higher energy than a Fermi energy of an electron in the localized electron region and permitting an electron to be confined in the respective localized electron regions, and a conductive electron region including a conductive electron system having a lower energy than an energy of the barrier potential region, wherein the respective localized electron regions are disposed separate from one another via the barrier potential region and the conductive electron region.

A self-organized magnetic array includes a plurality of magnetic primary nanoparticles are arranged on the substrate in a self-organized magnetic array. A plurality of magnetic interstitial nanoparticles are positioned between at least some of the primary nanoparticles in the self-organized magnetic array. A method of making such an array is also provided.

The invention discloses preparation and an application of a magnetic nanoring microwave absorbing agent, and particularly relates to a magnetic nanoring microwave absorbing agent with characteristics of good monodispersity and homogeneity, high magnetic responsiveness, excellent microwave absorbing performance, adjustable size and composition and the like as well as a preparation method and an application of the magnetic nanoring microwave absorbing agent. A magnetic nanoring adopts a polycrystalline structure formed by agglomeration of nanocrystallines and is oval, the length of a long axis is 28-175 nm, the length of a short axis is 18-130 nm, and the ring wall thickness is 7-35 nm; the magnetic nanoring comprises the component of Fe3O4, Fe3O4 / C or Fe / C with a spinel structure; ferric glycolate is taken as a precursor, and the magnetic nanoring is prepared by adopting an inert gas protective carbothermic reduction method-carbonization-solid-phase diffusion growth cooperation mechanism. The preparation and the application of the magnetic nanoring microwave absorbing agent are simple in process, low in cost and high in efficiency and facilitate industrial application and popularization, and the Fe3O4 and the carbon-magnetic nanoring have broad application prospects in the aspects of microwave absorption, a catalyst, an electrode material, a magnetic recording material, a biological sensor, separation or medical imaging.