The present invention relates to the field of magnetic assemblies and processes for producing optical effect layers (OELs) comprising magnetically oriented non-spherical magnetic or magnetizable pigment particles on a substrate. In particular, the present invention relates to magnetic assemblies processes for producing said OELs as anti-counterfeit means on security documents or security articles or for decorative purposes.

A spaser device comprises a graphene resonator and a carbon nanotube (CNT) gain element coupled via exciton-plasmon interaction. The graphene resonator may be a rectangular or square graphene nanoflake (GNF), and the CNT gain element may be characterised by chirality vector (n,m) selected such that the CNT has semiconducting properties. The CNT gain element may be illuminated using a light source having a photon energy corresponding with a first exciton energy (E.sub.22) of the CNT, whereby excitons having a second exciton energy (E.sub.11) less than the first exciton energy are generated in the CNT, and coupled to a surface plasmon (SP) mode of the graphene resonator. When the rate of generation of excitons having the second exciton energy exceeds a gain threshold, continuous spasing is established within the spaser device.

An electro-optical modulator using a graphene-based plasmonic slot is disclosed. The electro-optical modulator is comprised of a substrate layer, a dielectric spacer, a graphene layer, a first metal layer, and a second metal layer. The metal layers create a plasmonic slot that modulates between a light absorptive and light transparent state depending on the application of voltage across the modulator. Two or four graphene layers may be used to reduce power consumption and the size of the modulator.

The invention provides flash imaging devices that include an optical change component that undergoes a change in response to an applied stimulus, a substrate and a stimulus element. Also provided are articles that include the subject devices, as well as methods of making and using the same.

A reconfigurable polar molecule includes a symmetric nonpolar molecule portion having an elongated shape defined by a longitudinal axis and lateral axis, the longitudinal axis being longer than the lateral axis; a positive ionically charged group at a first end and a negative ionically charged group at a second end of the longitudinal axis, the positive and negative ionically charged groups forming a permanent dipole; a first bridging group and a second bridging group on opposing ends of the lateral axis, the first and second bridging groups being linear nonpolar groups; and a first support portion bonded to the first bridging group, and a second support portion bonded to the second bridging group, the first bridging group and the second bridging group being nonpolar and having structures that enable free rotation of the symmetric nonpolar molecule portion through the first bridging group and the second bridging group.

An optical modulation element 100 includes a rib type optical waveguide that includes a rib portion 112 that has a P-N junction, a P-type slab area 114 that continuously extends from a P type area of the rib portion 112, and an N-type slab area 116 that continuously extends from an N type area of the rib portion 112. A first thin film 130 is formed on the P-type slab area 114 and is made of a material having an electron affinity that is different from that of the P-type slab area 114.

The invention provides flash imaging devices that include an optical change component that undergoes a change in response to an applied stimulus, a substrate and a stimulus element. Also provided are articles that include the subject devices, as well as methods of making and using the same.

The invention provides flash imaging devices that include an optical change component that undergoes a change in response to an applied stimulus, a substrate and a stimulus element. Also provided are articles that include the subject devices, as well as methods of making and using the same.

Provided are an electronic paper display panel and a display device. The electronic paper display panel includes a first substrate and a second substrate opposite to each other and a plasma layer between the first substrate and the second substrate. The plasma layer includes an electrophoretic fluid and first-type charged particles. The first-type charged particles have charges with a first electrical property. The first-type charged particles include first charged subparticles and second charged subparticles. The particle size of a first charged subparticle is D.sub.1. The particle size of a second charged subparticle is D.sub.2. The charge quantity carried by the first charged subparticle is q.sub.1. The charge quantity carried by the second charged subparticle is q.sub.2. (D.sub.1-D.sub.2)(q.sub.1-q.sub.2)>0.

A spatial light modulator based on a metamaterial structure and a preparation method thereof. The spatial light modulator includes an array of optical function elements and a control circuit. The optical function element includes a metamaterial structure formed by a metal nanostructure layer and a metal reflector layer, with a medium layer and nonmetal conducting material layer being provided between the metal nanostructure layer and the metal reflector layer. The spatial light modulator is simple in structure, high in integration, easy in manufacture and low in cost. Furthermore, the spatial light modulator is capable of high-speed modulation, the depth of modulation is controlled easily, and a low drive voltage may be obtained.