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High carrier mobility and tunability in graphene enable fundamental studies for plasmonics and various applications. Despite its versatility, however, single‐layer graphene (SLG) suffers from poor coupling efficiency to electromagnetic waves, presenting a major challenge for photonic applications. Compared with visible or infrared radiation, terahertz (THz) waves exhibit higher absorption in SLG due to Drude‐like intraband transitions, but the wavelength‐to‐SLG size mismatch becomes even more dramatic. Here, we experimentally demonstrate 99% extinction of THz wave transmission when SLG covers the openings of 2‐nm‐wide (≈λ/1 000 000) slits through a metal film. By resonantly coupling THz waves through annular nanogaps, the extremely localized fields lead to near‐perfect extinction and strong absorption in SLG. Atomic‐layer lithography is used to produce these nanometer‐wide, millimeter‐long gaps over an entire 4‐in. wafer. Furthermore, by integrating these devices with an ionic liquid, enhanced intraband absorption in the SLG leads to 80% modulation of THz waves with an operational voltage as low as 1.5 V. [ABSTRACT FROM AUTHOR]

The ability to precisely control the topography, roughness, and chemical properties of metallic nanostructures is crucial for applications in plasmonics, nanofluidics, electronics, and biosensing. Here a simple method to produce embedded nanoplasmonic devices that can generate tunable plasmonic fields on ultraflat surfaces is demonstrated. Using a template-stripping technique, isolated metallic nanodisks and wires are embedded in optical epoxy, which is capped with a thin silica overlayer using atomic layer deposition. The top silica surface is topographically flat and laterally homogeneous, providing a uniform, high-quality biocompatible substrate, while the nanoplasmonic architecture hidden underneath creates a tunable plasmonic landscape for optical imaging and sensing. The localized surface plasmon resonance of gold nanodisks embedded underneath flat silica films is used for real-time kinetic sensing of the formation of a supported lipid bilayer and subsequent receptor-ligand binding. Gold nanodisks can also be embedded in elastomeric materials, which can be peeled off the substrate to create flexible plasmonic membranes that conform to non-planar surfaces. [ABSTRACT FROM AUTHOR]

Nanofabricated metallic tips are at the core of important research in single-molecule imaging, near-field scanning optical microscopy, tip-enhanced Raman spectroscopy, as well as potential commercial applications such as heat-assisted magnetic recording. While challenging to fabricate, much progress has been made towards the reliable production of extremely sharp (10 nm) metallic probes. In this review, the various factors that go into the design of metallic tips, their fabrication, packaging and system integration, characterization, passivation, and eventual use are discussed. Fabrication challenges, implementation issues, optical excitation schemes, and various current and emerging applications are also discussed. For the rapidly emerging fields of plasmonics and nanophotonics, the use of sharp metallic tips has generated significant scientific progress and will play an integral role well into the future. [ABSTRACT FROM AUTHOR]

The business-to-consumer aspect of electronic commerce (EC) is the most visible business use of the World Wide Web (WWW). A virtual store allows companies to provide product information and offer direct sales to their customers through an electronic channel. Success in this business is dependent on understanding the concerns of customers and identifying the factors that promote the intention to use a virtual store. Thus, this paper aims to examine the human motivations underlying individual behavioral intention to use a virtual store in Korea. This study employs TAM (technology acceptance model) as the base model and develops a more comprehensive version of TAM to better reflect a virtual store. The model employs playfulness, trust, information richness, and system quality, in addition to perceived usefulness and ease of use. The study investigates the causal relationships among the constructs used in this revised TAM and identifies the causal role of the constructs in developing the intention to use a virtual store. It finds that attitude toward a virtual store is the most significant factor in predicting the behavioral intention to use a virtual store. It also identifies perceived playfulness, perceived trust, perceived usefulness, and perceived ease of use as four major factors that directly affect virtual store users' attitudes. The results also indicate that information richness and system quality have significant albeit indirect impacts on consumer adoption of a virtual store. Considering the explosive growth of the virtual store market, a well-established business strategy in a virtual store will deliver great success to the virtual store operators. © 2009 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In article number 1801290 Yong‐Sang Ryu, Sang‐Hyun Oh, Sin‐Doo Lee, and co‐workers highlight that in a supported lipid bilayer membrane with alternating curvature the raft domains are initiated first in the leaflet with negative curvature and then appear later in the apposing leaflet which possesses positive curvature via inter‐leaflet coupling between the leaflets. This is confirmed by the spatial distribution of antibody binding to glycolipid receptors. [ABSTRACT FROM AUTHOR]

Membrane curvature is closely associated with spatial distribution of lipids and curvature can influence the formation of lipid rafts in biological membranes. However, it is still unclear how the curvature elasticity plays a role on the asymmetric distribution of lipids across the membrane leaflets, especially, during the process of the raft domain growth. Using supported lipid membranes on wedge‐shaped substrates with alternating positive and negative curvatures, curvature‐mediated asymmetry of lipid raft domains is observed across the membrane leaflets accompanied by glycolipid receptor (GM1 and GT1b) localization. The raft domains initially appear only in a membrane leaflet possessing negative curvatures. In the presence of the interleaflet coupling, they evolve to generate the transverse registry across the membrane bilayer. It is shown that a human recombinant antibody rHIgM12 is co‐localized with the rafts formed at the peaks and valleys of the wedge substrate, indicating that the spatial distribution of its receptor (GT1b) is indeed manifested by the site‐specific formation of asymmetric raft domains through the curvature elasticity. The platform can be used to explore the mechanism for the leaflet asymmetry and lipid sorting in terms of the membrane curvature, the composition, and the receptor presentation. Using supported lipid membranes on wedge‐shaped substrates, curvature‐mediated asymmetry of lipid raft domains is observed across the membrane leaflets accompanied by highly concentrated glycolipid receptors. The raft domains initially appear only in a membrane leaflet possessing negative curvatures. In the presence of the interleaflet raft coupling, they evolve to generate the transverse registry across the membrane bilayer. [ABSTRACT FROM AUTHOR]

On page 2812, Sang‐Hyun Oh and co‐workers report using template stripping to create embedded plasmonic nanodisks that can generate tunable plasmonic fields on ultraflat surfaces. The embedded nanodisks are topographically flat and capped with a silica layer to form a laterally homogeneous and biocompatible substrate. The nanoplasmonic architecture hidden underneath creates a tunable plasmonic landscape. Nanostructures can also be embedded in elastomeric materials, which can be peeled off the substrate to create flexible plasmonic membranes that conform to nonplanar surfaces. [ABSTRACT FROM AUTHOR]