Extraordinary optical transmission from a thin microcavity by macroscopic quantum effect

The macroscopic quantum effect is revealed to elaborate the extraordinary optical transmission (EOT) from a subwavelength thin microcavity based on the uncertainty property of the transmitted electromagnetic fields after the aperture. A critical radius is found in the thin microcavity under a certain incident electromagnetic wavelength. With the aperture radius varying, the transmitted field can be divided into three regimes: I. the macroscopic quantum regime when the aperture radius is less than the critical radius, in which the field edge effect occurs and EOT phenomenon is perfectly manifested; II. The wave-particle duality regime in the vicinity of the critical radius, in which the edge effect and diffraction phenomenon exist simultaneously; III. The wave regime when the aperture radius is greater than the critical radius, in which the near-field diffraction emerges. In addition, the influences of incident wavelength and microcavity thickness on EOT are also investigated. Our research have potential applications in advanced optical devices, such as light switch and optical manipulations.

Metallurgical Behavior of Amorphous Alloy during Annealing at Different Temperatures via Molecular Dynamics Simulation

The mechanism of annealing-induced amorphization of metallic glass is investigated in this study via molecular dynamics simulation. Spherical nucleuses of Cu–Ni–Al alloy with a face-centered cubic structure are embedded to simulate nanograins in Cu–Ni–Al amorphous alloy; subsequently, the material is annealed at different temperatures. The results show that the critical radius for nucleation at temperatures above the glass transition temperature (Tg) affected the behavior, grain growth, and annihilation of nanograins in the Cu–Ni–Al amorphous alloy during annealing. When the temperature increased, the critical radius for nucleation increased as well. This causes the small nanograins to annihilate quickly and the large nanograins to develop rapidly. When the annealing temperature is higher than Tg, part of the crystal nuclei, which is smaller than the critical radius, can be eliminated. The crystallinity of the metallic glass decreased, and the minimum crystallinity is attained after a period of annealing simulation. Subsequently, as the residual effective nanograins began developing, the crystallinity of the amorphous metal increased again. Therefore, the annealing duration time is critical to the crystallinity of the amorphous alloy after annealing.

Synthesis of Vortex Rossby Waves. Part III: Rossby Waveguides, Vortex Motion, and the Analogy with Middle-Latitude Cyclones

Vortex Rossby Waves (VRWs) affect Tropical Cyclones’ (TCs’) motion, structure, and intensity. They propagate within annular waveguides defined by a passband between Ω1D, the Doppler-shifted frequency of a one-dimensional VRW, and zero. Wavenumber-1 VRWs cause TC motion directly and have wider waveguides than wavenumbers ≥ 2. VRWs forced with fixed rotation frequency propagate away from the forcing. Initially outward-propagating waves are Doppler shifted to zero at a critical radius, where they are absorbed. Initially inward-propagating waves are Doppler-shifted to Ω1D, reflect from a turning point, propagate outward, and are ultimately absorbed at the critical radius. Between the forcing and the turning radii, the VRWs have standing-wave structure; outward from the forcing they are trailing spirals. They carry angular momentum fluxes that act to accelerate the mean flow at the forcing radius and decelerate it at the critical radius.Mean flow vorticity monopoles are inconsistent with Stokes Theorem on a spherical Earth, because a contour enclosing the monopole’s antipode would have nonzero circulation but would enclose zero vorticity.The Rossby waveguide paradigm also fits synoptic-scale Rossby Waves in a meridionally sheared zonal flow. These waves propagate within a waveguide confined between a poleward turning latitude and an equatorward critical latitude. Forced waves are comma-shaped gyres that resemble observed frontal cyclones, with trailing filaments equatorward of the forcing latitude and standing waves poleward. Even neutral forced Rossby waves converge westerly momentum at the latitude of forcing.

Electric-Potential-Assisted Crystallisation of L-Isoleucine: A Study of Nucleation Kinetics and Its Associated Parameters

The potential of producing L-isoleucine crystals with the aid of electric potential and its effect on the nucleation kinetics of L-isoleucine were probed using polythermal and isothermal crystallisation techniques, assisted with 5 V, 9 V, and 20 V electric potentials. The polythermal experiments were conducted with cooling rates of 0.1 °C/min–0.7 °C/min, whilst isothermal crystallisation was conducted with a supersaturation of 1.30–1.70, and both were carried out in a 200 mL temperature-controlled jacketed reactor. Prediction of the nucleation rate and its associated parameters for isothermal crystallisation was carried out using a molecular dynamics simulation. In both crystallisation techniques, electric potentials increased the nucleation rate, but the intensity of the electric potential had less impact on the measured parameters. Nucleation rates for 5 V isothermal crystallisation were in the order of 1010 higher than for polythermal crystallisation. Electric potential doubled the nucleation rates for polythermal crystallisation and increased the nucleation rates 12-fold in isothermal crystallisation. The isothermal technique produced the form B polymorph, but mixtures of forms A and B were produced in polythermal crystallisation. The predicted critical number of molecules, N*, and the critical radius, r*, were in good agreement with the experimental data, with a higher predicted nucleation rate in the order of 102.

A study on causality in f(R,ϕ,X) theory

The [Formula: see text]-essence modified [Formula: see text] gravity model, i.e. [Formula: see text] theory is studied. The question of violation of causality, in the framework of Gödel-type universes, is investigated in this gravitational model. Causal and noncausal solutions are allowed. A critical radius for noncausal solution is calculated. It is shown that the violation of causality depends on the content of matter.

Correlating oxygen mobility with thermochemical CO2-splitting efficiency in A-site substituted perovskites

The effect of lattice geometric parameters of perovskite oxides on thermochemical redox CO2-splitting process was highlighted. Experimentally-derived amounts of O2 and CO evolved were found to correlate with critical radius...

Gödel and Gödel-type solutions in the Palatini f(R,T) gravity theory

The Palatini [Formula: see text] gravity theory is considered. The standard Einstein–Hilbert action is replaced by an arbitrary function of the Ricci scalar [Formula: see text] and of the trace [Formula: see text] of the energy-momentum tensor. In the Palatini approach, the Ricci scalar is a function of the metric and the connection. These two quantities, metric and connection, are taken as independent variables. Then, it is examined whether Palatini [Formula: see text] gravity theory allows solutions in which lead to violation of causality. The Gödel and Gödel-type spacetimes are considered. In addition, a critical radius, which permits to examine limits for violation of causality, is calculated. It is shown that, for different matter contents, noncausal solutions can be avoided in this Palatini gravitational theory.