A proposal for a new type of thin-film field-emission display by edge breakdown of MIS structure

A new type of field emission display(FED) based on an edge-enhance electron emission from metal-insulator-semiconductor (MIS) thin film structure is proposed. The electrons produced by an avalanche breakdown in the semiconductor near the edge of a top metal electrode are initially injected to the thin film of an insulator with a negative electron affinity (NEA), and then are injected into vacuum in proximity to the top electrode edge. The condition for the deep-depletition breakdown near the edge of the top metal electrode is analytically found in terms of ratio of the insulator thickness to the maximum (breakdown) width of the semiconductor depletition region: this ratio should be less than 2/(3 \pi - 2) = 0.27. The influence of a neighboring metal electrode and an electrode thickness on this condition are analyzed. Different practical schemes of the proposed display with a special reference to M/CaF_2/Si structure are considered.Comment: 11 pages, 5 figure

Size-dependent hydrogen uptake behavior of Pd nanoparticles revealed by photonic crystal surface waves

We present an optical method of study of nanoparticle properties using photonic crystal surface waves. Palladium nanoparticles were deposited on a surface of a one-dimensional photonic crystal, which supports the propagation of p-polarized optical surface waves. The changes in the nanoparticle properties, such as its dimension and refractive index, were monitored through angle interrogation of the photonic crystal surface waves. The interaction of palladium nanoparticles with hydrogen was detected with this method. The size-different hydrogen uptake behavior by 2 and 6 nm diameter Pd nanoparticles results in qualitatively different response of the optical signal, viz., in the different signs of such a response. This not only confirms the absence of the alpha- to beta-phase transformation for the smallest palladium nanoparticles, but is a plausible indication that hydrogen donates its electrons to a collective electron band of the metal. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3690085

Article Photonic Crystal Biosensor Based on Optical Surface Waves

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Registration of long-range surface plasmon resonance by angle-scanning feedback and its implementation for optical hydrogen sensing

An optical technique devised for the detection of the ultrasharp angular resonance of long-range surface plasmons (LRSPs) is described. The LRSPs propagate along an 8 nm-thick palladium (Pd) film deposited on a one- dimensional photonic crystal structure and bordering a gas environment at another Pd film interface. At such a small metal film thickness, the scattering attenuation losses prevail over dissipation losses inside the film and we use this scattering as an input signal to pick up the angle of the surface plasmon resonance by a closed feedback loop via an angle-scanning piezomirror. As an implementation of this technique, we detected a 0.5% hydrogen concentration in nitrogen at room temperature with a signal/noise ratio of approximately 100 and response and recovery times of about 5 and 15 s, respectively