Abstract: Described herein is a process of preparing a structural colored coating film including steps of i) applying colloidal particles dispersed in a solvent mixture including at least two organic solvents onto a substrate to form a colloidal particles layer; ii) drying the colloidal particles layer to form a photonic crystal structure layer; iii) applying a coating composition including at least one thermally crosslinkable resin and at least one crosslinking agent onto the photonic crystal structure layer to form a coating; and iv) heat curing. Also described herein is an article having at least one structural colored coating film obtainable or obtained from the process.

Abstract: Embodiments of the present application provide a bi-directional optical sub-assembly and an optical module, including: a laser chip, a Faraday rotator, a polarization detection filter, a detector chip, and an optical fiber ferrule; the laser chip, the Faraday rotator, the polarization detection filter and the optical fiber ferrule are sequentially disposed on a first optical axis; after polarized light emitted by the laser chip is rotated by the Faraday rotator, a direction of state of polarization of the polarized light is as same as a direction of polarization detection of the polarization detection filter; the rotated polarized light is then injected into the optical fiber ferrule for transmission, and light from the optical fiber ferrule is injected into the detector chip after being reflected by the polarization detection filter.

Abstract: Provided is a method of forming a microsphere having a structural color, which includes providing a composition for generating a structural color including a curable material and magnetic nanoparticles dispersed in the curable material, forming an emulsion by adding the composition for generating a structural color to an immiscible solvent, arranging the magnetic nanoparticles located in the emulsion droplet of the curable material in a one-dimensional chain structure by applying a magnetic field to the emulsion, and fixing the chain structure by curing the emulsion droplet.

Abstract: Monodisperse colloidal nanocrystal clusters of magnetite (Fe3O4) with tunable sizes from about thirty to about three hundred nanometers have been synthesized using a high-temperature hydrolysis process. The colloidal nanocrystal clusters are capped with polyelectrolytes, and highly water soluble. Each cluster is composed of many single magnetite crystallites, thus retaining the superparamagnetic behavior at room temperature. The combination of superparamagnetic property, high magnetization, and high water dispersibility makes the colloidal nanocrystal clusters ideal candidates for various important biomedical applications such as drug delivery and bioseparation. The present invention is further directed to methods for forming colloidal photonic crystals from both aqueous and nonaqueous solutions of the superparamagnetic colloidal nanocrystal clusters with an external magnetic field applied thereto.

Abstract: A method of assembling superparamagnetic colloids into ordered structures with magnetically tunable photonic properties in nonpolar solvents by establishing long-range electrostatic repulsive forces using charge control agents. Reverse micelles resulted from the introduction of charge control agents such as AOT molecules can enhance the charge separation on the surfaces of n-octadecyltrimethoxysilane modified Fe3O4@SiO2 particles. The significantly improved long-range electrostatic repulsion can counterbalance the magnetically induced attraction and therefore allow ordering of superparamagnetic colloids in nonpolar solvents. This system possesses fast and fully reversible optical response to the external magnetic fields, long-term stability in performance, and good diffraction intensity.

Abstract: Provided is a method of forming a microsphere having a structural color, which includes providing a composition for generating a structural color including a curable material and magnetic nanoparticles dispersed in the curable material, forming an emulsion by adding the composition for generating a structural color to an immiscible solvent, arranging the magnetic nanoparticles located in the emulsion droplet of the curable material in a one-dimensional chain structure by applying a magnetic field to the emulsion, and fixing the chain structure by curing the emulsion droplet.

Abstract: Compositions and methods wherein ordered structures of photonic nanocrystals are created in a liquid medium and then such structures are fixed by converting the liquid medium to a solid. In addition, compositions and methods of reversibly fixing such structures, so that ordered structures can be reversibly created in a liquid medium, converted to solid, and then converted back to liquid, wherein new ordered structures can be created and again fixed.

Abstract: A method of assembling superparamagnetic colloids into ordered structures with magnetically tunable photonic properties in nonpolar solvents by establishing long-range electrostatic repulsive forces using charge control agents. Reverse micelles resulted from the introduction of charge control agents such as AOT molecules can enhance the charge separation on the surfaces of n-octadecyltrimethoxysilane modified Fe3O4@SiO2 particles. The significantly improved long-range electrostatic repulsion can counterbalance the magnetically induced attraction and therefore allow ordering of superparamagnetic colloids in nonpolar solvents. This system possesses fast and fully reversible optical response to the external magnetic fields, long-term stability in performance, and good diffraction intensity.

Abstract: Monodisperse colloidal nanocrystal clusters of magnetite (Fe3O4) with tunable sizes from about thirty to about three hundred nanometers have been synthesized using a high-temperature hydrolysis process. The colloidal nanocrystal clusters are capped with polyelectrolytes, and highly water soluble. Each cluster is composed of many single magnetite crystallites, thus retaining the superparamagnetic behavior at room temperature. The combination of superparamagnetic property, high magnetization, and high water dispersibility makes the colloidal nanocrystal clusters ideal candidates for various important biomedical applications such as drug delivery and bioseparation. The present invention is further directed to methods for forming colloidal photonic crystals from both aqueous and nonaqueous solutions of the superparamagnetic colloidal nanocrystal clusters with an external magnetic field applied thereto.