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We present our experimental demonstration of self-collimation inside a three-dimensional (3D) simple cubic photonic crystal at microwave frequencies. The photonic crystal was designed with unique dispersion property and fabricated by a high precision computer-controlled machine. The self-collimation modes were excited by a grounded waveguide feeding and detected by a scanning monopole. Self-collimation of electromagnetic waves in the 3D photonic crystal was demonstrated by measuring the 3D field distribution, which was shown as a narrow collimated beam inside the 3D photonic crystal but a diverged beam in the absence of the photonic crystal.

In this paper, we present novel designs and analysis of ultra-compact couplers and 1 x 2 splitters based on plasmonic waveguides. Numerical simulation shows coupling efficiency up to 88% for the former one and 45% for each branch for the latter one. The proposed coupler design has the advantages of improving the alignment tolerance of the plasmonic waveguide with respect to the dielectric waveguide and broadening the spectrum response of the splitter.

We experimentally demonstrate subwavelength resolution imaging at microwave frequencies by a three-dimensional (3D) photonic-crystal flat lens using full 3D negative refraction. The photonic crystal was fabricated in a layer-by-layer process. A subwavelength pinhole source and a dipole detector were employed for the measurement. By point-by-point scanning, we obtained the image of the pinhole source shown in both amplitude and phase, which demonstrated the imaging mechanism and subwavelength feature size in all three dimensions. An image of two pinhole sources with subwavelength spacing showed two resolved spots, which further verified subwavelength resolution.

Silver nanoparticles deposited on TiO2 nanoporous films exhibited unique photochromic property under the irradiation of visible light. Here we investigated the application of photochromic Ag/TiO2 nanocomposite film in holographic data storage. Stable holographic fringes were formed on the Ag/TiO2 film using two coherent green lasers as writing beams, and these fringes could be erased with ultraviolet irradiation. These observations are consistent with the photochromism of Ag/TiO2 nanocomposite film and can be well explained by the visible light-stimulated dissolution and ultraviolet light-stimulated regeneration of silver nanoparticles in TiO2 matrix.

We report a broadband electro-optical (EO) modulator based on tunable plasmonic metamaterial. Transparent conducting oxides provide an excellent active plasmonic material for optoelectronic applications. By utilizing our indium-tin-oxide- (ITO) based multilayer structure, light absorption of the active ITO layer can be electrically modulated over a large spectrum range. Based on the attenuated total reflectance configuration, bias polarity-dependent modulation up to 37% has been experimentally demonstrated. This EO modulator has advantages of simple design, easy fabrication, compact size, broadband performance, large modulation depth, as well as compatibility with existing silicon photonics platforms.

Recent work demonstrated light transmission through deep subwavelength slits or coupling light into waveguides with deep subwavelength dimension only in one direction. In this paper, we propose an approach to squeeze light (lambda = 1550 nm) from a dielectric waveguide into a deep subwavelength spot. Vertical confinement is achieved by efficiently coupling light from a dielectric waveguide into a 20-nm metal-dielectric-metal plasmonic waveguide. The horizontal dimension of the plasmonic waveguide is then tapered into 20 nm. Numerical simulation shows that light fed from a dielectric waveguide can be squeezed into a 21 nm-by-24 nm spot with efficiency 62%.

Action real-time strategy gaming (ARSG)-a major genre of action video gaming (AVG)-has both action and strategy elements. ARSG requires attention, visual working memory (VWM), sensorimotor skills, team cooperation, and strategy-making abilities, thus offering promising insights into the learning-induced plasticity. However, it is yet unknown whether the ARSG experience is related to the development of VWM capacity. Using both behavioral and event-related potential (ERP) measurements, this study tested whether ARSG experts had larger VWM capacity than non-experts in a change detection task. The behavioral results showed that ARSG experts had higher accuracy and larger VWM capacity than non-experts. In addition, the ERP results revealed that the difference wave of the contralateral delay activity (CDA) component (size 4-size 2) elicited by experts was significantly larger than that of non-experts, suggesting that the VWM capacity was higher in experts than in non-experts. Thus, the findings suggested that prolonged ARSG experience is correlative with the enhancement of VWM.