Electrons living in a two-dimensional world under a strong magnetic field -the socalled fractional quantum Hall effect (FQHE) -often manifest themselves as fractionally charged quasiparticles (anyons). Moreover, being under special conditions they are expected to be immune to the environment, thus may serve as building blocks for future quantum computers. Interference of such anyons is the very first step towards understanding their anyonic statistics. However, the complex edge-modes structure of the fractional quantum Hall states, combined with upstream neutral modes, have been suspected to prevent an observation of the much sought after interference of anyons. Here, we report of finding a direct correlation between the appearance of neutral modes and the gradual disappearance of interference in a Mach-Zehnder interferometer (MZI), as the bulk filling factor is lowered towards Landau filling =1; followed by a complete interference quench at =1. Specifically, the interference was found to start diminishing at ~1.5 with a growing upstream neutral mode, which was detected by a born upstream shot noise in the input quantum point contact (QPC) to the MZI. Moreover, at the same time a =1/3 conductance plateau, carrying shot-noise, appeared in the transmission of the QPC -persisting until bulk filling =1/2. We identified this conductance plateau to result from edge reconstruction, which leads to an upstream neutral mode. Here, we also show that even the particle-like quasiparticles are accompanied by upstream neutral modes, therefore suppressing interference in the FQHE regime.

Solid-state electronic transport (ETp) via the electron-transfer copper protein azurin (Az) was measured in Au/Az/Au junction configurations down to 4 K, the lowest temperature for solid-state protein-based junctions. Not only does lowering the temperature help when observing fine features of electronic transport, but it also limits possible electron transport mechanisms. Practically, wire-bonded devices-on-chip, carrying Az-based microscopic junctions, were measured in liquid He, minimizing temperature gradients across the samples. Much smaller junctions, in conducting-probe atomic force microscopy measurements, served, between room temperature and the protein’s denaturation temperature (∼323 K), to check that conductance behavior is independent of device configuration or contact nature and thus is a property of the protein itself. Temperature-independent currents were observed from ∼320 to 4 K. The experimental results were fitted to a single-level Landauer model to extract effective energy barrier and electrode–molecule coupling strength values and to compare data sets. Our results strongly support that quantum tunneling, rather than hopping, dominates ETp via Az.

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Abstract-We consider the problem of streaming live content to a cluster of co-located wireless devices that have both an expensive unicast base-station-to-device (B2D) interface, as well as an inexpensive broadcast device-to-device (D2D) interface, which can be used simultaneously. Our setting is a streaming system that uses a block-by-block random linear coding approach to achieve a target percentage of on-time deliveries with minimal B2D usage. Our goal is to design an incentive framework that would promote such cooperation across devices, while ensuring good quality of service. Based on ideas drawn from truth-telling auctions, we design a mechanism that achieves this goal via appropriate transfers (monetary payments or rebates) in a setting with a large number of devices, and with peer arrivals and departures. Here, we show that a Mean Field Game can be used to accurately approximate our system. Furthermore, the complexity of calculating the best responses under this regime is low. We implement the proposed system on an Android testbed, and illustrate its efficient performance using real world experiments.

Metal oxide semiconductors (MOS) are well known as reducing gas sensors. However, their selectivity and operating temperature have major limitations. Most of them show cross sensitivity and the operating temperatures are also relatively higher than the value reported here. To resolve these problems, here, we report the use of palladium−silver (70−30%) activated ZnO thin films as a highly selective methane sensor at low operating temperature (∼100 °C). Porous ZnO thin films were deposited on fluorinedoped tin oxide (FTO)-coated glass substrates by galvanic technique. X-ray diffraction showed polycrystalline nature of the films, whereas the morphological analyses (field emission scanning electron microscopy) showed flake like growth of the grains mainly on xy plane with high surface roughness (107 nm). Pd−Ag (70−30%) alloy was deposited on such ZnO films by ebeam evaporation technique with three different patterns, namely, random dots, ultrathin (∼1 nm) layer and thin (∼5 nm) layer as the activation layer. ZnO films with Pd−Ag dotted pattern were found show high selectivity towards methane (with respect to H 2 S and CO) and sensitivity (∼80%) at a comparatively low operating temperature of about 100°C. This type of sensor was found to have higher methane selectivity in comparison to other commercially available reducing gas sensor.