We show optical waves passing through a nanophotonic medium can perform artificial neural computing. Complex information, is encoded in the wave front of an input light. The medium transforms the wave front to realize sophisticated computing tasks such as image recognition. At the output, the optical energy is concentrated to well-defined locations, which for example can be interpreted as the identity of the object in the image. These computing media can be as small as tens of wavelengths and offer ultra-high computing density. They exploit sub-wavelength scatterers to realize complex input output mapping beyond the capabilities of traditional nanophotonic devices.

Recent years have witnessed significant interest in nanoscale physical systems, such as nanoelectromechanical and optomechanical systems, which can exhibit distinct collective dynamical behaviors, such as synchronization. As a parameter of the system changes, transition from one type of emerging collective behavior to another can occur. But what are the quantum manifestations of such a transition? We investigate a system of two optically coupled optomechanical cavities and uncover the phenomenon of transition from in-phase to antiphase synchronization. Quantum mechanically, we find that, associated with the classical transition, the entanglement measures between the various optical and mechanical degrees of freedom in the two cavities exhibit a change characteristic of second-order phase transition. These phenomena can be tested experimentally.

In patients with normal or mildly impaired renal function, dapagliflozin is not associated with increased risk of acute renal toxicity or deterioration of renal function. All trials included in this analysis are registered at ClinicalTrials.gov: NCT00263276, NCT00972244, NCT00528372, NCT00736879, NCT00528879, NCT00855166, NCT00357370, NCT00680745, NCT00683878, NCT00673231, NCT00643851, NCT00859898.

We review recent progress in modelling the probability distribution of wave heights in the deep ocean as a function of a small number of parameters describing the local sea state. Both linear and nonlinear mechanisms of rogue wave formation are considered. First, we show that when the average wave steepness is small and nonlinear wave effects are subleading, the wave height distribution is well explained by a single 'freak index' parameter, which describes the strength of (linear) wave scattering by random currents relative to the angular spread of the incoming random sea. When the average steepness is large, the wave height distribution takes a very similar functional form, but the key variables determining the probability distribution are the steepness, and the angular and frequency spread of the incoming waves. Finally, even greater probability of extreme wave formation is predicted when linear and nonlinear effects are acting together.

A seasonal trend analysis of published Dobson (including stations' newly revised and Brewer‐simulated Dobson) total ozone data through 1991 from a network of 56 stations has been performed, using three different data periods. The trend results for the longest data period 1964–1991 indicate substantial negative trends in ozone in the higher northern latitudes during the winter and spring seasons, some evidence of negative trend in the higher southern latitudes (30°S–55°S) during all seasons, and trends close to zero for all seasons over the 30°S–30°N latitude range. For the shortest data period, November 1978 through 1991, there is a clear indication that trends have become more negative in the higher northern latitudes, especially during the winter and spring seasons, and also in the higher southern latitudes in all seasons. A seasonal trend analysis of zonal averages of total ozone mapping spectrometer (TOMS) satellite total ozone data for the comparable period November 1978 through 1991 has also been performed, and moderately good agreement is found between trends in Dobson and TOMS data over this period.

An outstanding and fundamental problem in contemporary physics is to include and probe the many-body effect in the study of relativistic quantum manifestations of classical chaos. We address this problem using graphene systems described by the Hubbard Hamiltonian in the setting of resonant tunneling. Such a system consists of two symmetric potential wells separated by a potential barrier, and the geometric shape of the whole domain can be chosen to generate integrable or chaotic dynamics in the classical limit. Employing a standard mean-field approach to calculating a large number of eigenenergies and eigenstates, we uncover a class of localized states with near-zero tunneling in the integrable systems. These states are not the edge states typically seen in graphene systems, and as such they are the consequence of many-body interactions. The physical origin of the non-edge-state type of localized states can be understood by the one-dimensional relativistic quantum tunneling dynamics through the solutions of the Dirac equation with appropriate boundary conditions. We demonstrate that, when the geometry of the system is modified to one with chaos, the localized states are effectively removed, implying that in realistic situations where many-body interactions are present, classical chaos is capable of facilitating greatly quantum tunneling. This result, besides its fundamental importance, can be useful for the development of nanoscale devices such as graphene-based resonant-tunneling diodes.

Nonhyperbolicity, as characterized by the coexistence of Kolmogorov-Arnold-Moser (KAM) tori and chaos in the phase space, is generic in classical Hamiltonian systems. An open but fundamental question in physics concerns the relativistic quantum manifestations of nonhyperbolic dynamics. We choose the mushroom billiard that has been mathematically proven to be nonhyperbolic, and study the resonant tunneling dynamics of a massless Dirac fermion. We find that the tunneling rate as a function of the energy exhibits a striking "clustering" phenomenon, where the majority of the values of the rate concentrate on a narrow region, as a result of the chaos component in the classical phase space. Relatively few values of the tunneling rate, however, spread outside the clustering region due to the integrable component. Resonant tunneling of electrons in nonhyperbolic chaotic graphene systems exhibits a similar behavior. To understand these numerical results, we develop a theoretical framework by combining analytic solutions of the Dirac equation in certain integrable domains and physical intuitions gained from current understanding of the quantum manifestations of chaos. In particular, we employ a theoretical formalism based on the concept of self-energies to calculate the tunneling rate and analytically solve the Dirac equation in one dimension as well as in two dimensions for a circular-ring-type of tunneling systems exhibiting integrable dynamics in the classical limit. Because relatively few and distinct classical periodic orbits are present in the integrable component, the corresponding relativistic quantum states can have drastically different behaviors, leading to a wide spread in the values of the tunneling rate in the energy-rate plane. In contrast, the chaotic component has embedded within itself an infinite number of unstable periodic orbits, which provide far more quantum states for tunneling. Due to the nature of chaos, these states are characteristically similar, leading to clustering of the values of the tunneling rate in a narrow band. The appealing characteristic of our work is a demonstration and physical understanding of the "mixed" role played by chaos and regular dynamics in shaping relativistic quantum tunneling dynamics.

Structural order beyond the next-nearest-neighbor structural units is of great interest in network glasses, especially in chalcogenide glasses, but little specific description can be reached. Here, the structure of pseudobinary (100 − x)GeS 2 −xSb 2 S 3 chalcogenide glasses is elucidated using differential scanning calorimetry, Raman scattering, and laser-induced phase transformation experiments over its full range (0 ≤ x ≤ 100) of compositions. We observe two compositional thresholds of x = 40 and 50 in the calorimetric experiments, which are confirmed by Raman scattering and laser-induced phase transformation studies, respectively. Three structural features can be derived from these results: the structural motifs in this glass network are the [SbS 3 ] pyramid and [GeS 4 ] tetrahedra, respectively; at x ≥ 40, the connection between [GeS 4 ] tetrahedra vanishes; and at x ≥ 50, the aggregation of four [SbS 3 ] units happens, preparing for the laser-induced crystallization of Sb 2 S 3 crystallites. Combined with valuable indication from the topological thresholds, a specific structural model covering the arrangement of structural units in a large atomic scale is clarified, which can perfectly explain all the experimental results. This work provides a new way to get insight into the intermediate-range order of glass networks and understand their related physical properties.