Apparatuses for manipulating a color displayed by an article of wear comprising iron oxide colloidal nanocrystals arranged within chains are described. The apparatus includes (a) a magnetic field source, wherein a strength of a magnetic field generated by the magnetic field source is tunable to control the color displayed by the article of wear, and (b) an energy source, wherein energy generated by the energy source is applied to at least some of the chains of nanocrystals to soften materials within the article of wear immediately surrounding the chains of nanocrystals to which the energy is applied.

The present application is directed in various illustrative embodiments to an optical waveguide, an optical waveguide system with such an optical waveguide, a light energy storage structure, light confining structures, a light energy storage system and an energy storage and/or conversion system with such an optical waveguide system. In an aspect, an optical waveguide is provided, comprising an optical fiber with a fiber core and an optical active cladding structure over at least a portion of the fiber core at a first end of the optical waveguide, wherein the optical active cladding structure comprises a Bragg mirror stacking having a high transmittance in a first wavelength region and a high reflectivity in a second wavelength region of wavelengths longer than wavelengths in the first wavelength region, and a wavelength conversion coating over the fiber core of the optical fiber. The wavelength conversion coating is configured to convert radiation with wavelengths in the first wavelength region into radiation with wavelengths in the second wavelength region and the Bragg mirror stacking is disposed over the wavelength conversion coating.

Switches for electromagnetic radiation, including radiofrequency switches and optical switches, are provided. Also provided are methods of using the switches. The switches incorporate layers of high quality VO.sub.2 that are composed of a plurality of connected crystalline VO.sub.2 domains having the same crystal structure and orientation.

A method includes depositing a layer of silicon oxide onto a layer of silicon carbide; ion implanting the layer of silicon carbide, annealing the ion implanted layer of silicon carbide to produce defects within the layer of silicon carbide, performing photolithography using a mask layer on regions of the layer of silicon carbide to define regions for electrode deposition, removing the layer of silicon oxide from the layer of silicon carbide in the one or more regions for electrode deposition, forming one or more electrodes by depositing indium tin oxide (ITO) in each of the regions for electrode deposition, performing a first lift-off operation to remove the mask layer surrounding the electrodes, depositing a passivation and gate silicon oxide layer on top of the layer of silicon carbide and the electrodes, and performing a second lift-off operation to fabricate an optically transparent ITO gate between the electrodes.

Provided herein is a phase change material for use in a display device. Also provided is a display device comprising a phase change material; the use of a phase change material as an optical absorber in a display device; a method of fabricating a pixel; and a method of fabricating a display device. The phase change material is as described in more detail herein.

Embodiments of the present disclosure relate to a programmable metamaterial which comprises an array of phase-change material elements. A domain inducing component may be coupled to at least one phase-change material element of the array of phase-change material elements. The domain inducing component may be configured to program the refractive index of the at least one phase-change material element and reprogram the refractive index of the at least one phase-change material element by inducing a phase transition in a domain of the at least one phase-change material element. A method for programming the metamaterial may include selecting the phase-change material element for programming and programming the refractive index of the selected phase-change material element by inducing a phase transition in a domain of the selected phase-change material element.

Switches for electromagnetic radiation, including radiofrequency switches and optical switches, are provided. Also provided are methods of using the switches. The switches incorporate layers of high quality VO.sub.2 that are composed of a plurality of connected crystalline VO.sub.2 domains having the same crystal structure and orientation.

A fast optical switch can be fabricated/constructed, when a vanadium dioxide (VO.sub.2) and a two-dimensional (2-D) material is activated by either an electrical pulse (a voltage pulse or a current pulse) or a light pulse just to induce an insulator-to-metal phase transition (IMT) in vanadium dioxide. The applications of such a fast optical switch for an on-demand optical add-drop subsystem, integrating with (a) a light slowing/light stopping component (based on metamaterials and/or nanoplasmonic structures) and (b) with or without a wavelength converter are also described.

The invention relates to doping capsules which have a substance which displays a decreasing transparency with increasing temperature within a defined temperature range due to physicochemical interactions with the polymer matrix to be doped. Likewise, the invention relates to composite systems which have a polymer matrix doped with the doping capsules. The capsules according to the invention are used for sun protection or heat reflection.

Provided herein is a phase change material for use in a display device. Also provided is a display device comprising a phase change material; the use of a phase change material as an optical absorber in a display device; a method of fabricating a pixel; and a method of fabricating a display device. The phase change material is as described in more detail herein.