We experimentally demonstrate the emergence of a purely azimuthally polarized vectorial vortex beam with a phase singularity upon Brewster reflection of focused circularly polarized light from a dielectric substrate. The effect originates from the polarizing properties of the Fresnel reflection coefficients described in Brewster's law. An astonishing consequence of this effect is that the reflected field's Cartesian components acquire local phase singularities at Brewster's angle. Our observations are crucial for polarization microscopy and open new avenues for the generation of exotic states of light based on spin-to-orbit coupling, without the need for sophisticated optical elements.

The reliability of predictive and management models for ground water would be improved by better aquifer‐parameter estimation. As progress continues in the use of computers to simulate ground‐water systems, parallel progress must occur in data collection and analysis. Among the various methods available for the determination of aquifer parameters, pumping tests occupy a prominent position. The maximum advantage is gained from a pumping test when geological knowledge of the aquifer and the analysis of aquifer test data complement each other. This paper presents a technique involving the use of convolution and sensitivity analysis to obtain the “best fit” of aquifer parameters in a least‐squares sense from a pumping test with variable pumping rate. The method also can be used to analyze the residual drawdown data obtained during the recovery period. In addition, this method can also analyze drawdown and recovery data conjunctively. Constant drawdown and variable discharge data of artesian flowing wells also can be analyzed by this method. The method is straightforward, quick, inexpensive, and is always objective. No graphical plots or graphical interpretations are needed. As a measure of error, the rms (root‐mean‐square) error in drawdown is calculated along with the correlation coefficient between pumping‐test data and the theoretically generated data, using the converged values of transmissivity and storage coefficient.

In the last decade, nano-optics has emerged as a scientific field, pushing the boundaries of science. [1] A very important subcategory of this field is the study and fabrication of various 2D and 3D artificial materials, based on layers of structured dielectrics and metals. [2] The reason for the interest in these metamaterials and metasurfaces is the vast variety of applications, such as guiding, shaping, and focusing of light beams, the development of ultrathin highly efficient polarizing elements and many more. [3] Recently, orthorhombic carbon phase structures were theoretically predicted, with enhanced optical and structural properties. [4][5][6][7] Carbon allotropes and carbon hybrid materials with embedded metal structures, have been proven to be a beneficial building-block in opto-electronicCarbon-based and carbon-metal hybrid materials hold great potential for applications in optics and electronics. Here, a novel material made of carbon and gold-silver nanoparticles is discussed, fabricated using a laser-induced self-assembly process. This self-assembled metamaterial manifests itself in the form of cuboids with lateral dimensions on the order of several micrometers and a height of tens to hundreds of nanometers. The carbon atoms are arranged following an orthorhombic unit cell, with alloy nanoparticles intercalated in the crystalline carbon matrix. The optical properties of this metamaterial are analyzed experimentally using a microscopic Müller matrix measurement approach and reveal a high linear birefringence across the visible spectral range. Theoretical modeling based on local-field theory applied to the carbon matrix links the birefringence to the orthorhombic unit cell, while finite-difference time-domain simulations of the metamaterial relates the observed optical response to the distribution of the alloy nanoparticles and the optical density of the carbon matrix. Orthorhombic Carbon@Au-AgThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.

Asymmetric transmission—direction-selective electromagnetic transmission between two ports—is a phenomenon exhibited by two-dimensional chiral systems. The possibility of exploiting this phenomenon in chiral metasurfaces opens exciting possibilities for applications such as optical isolation and routing without external magnetic fields. This work investigates optical asymmetric transmission in chiral plasmonic metasurfaces supporting lattice plasmon modes and unveils its physical origins. We show numerically and experimentally that asymmetric transmission is caused by an unbalanced excitation of such lattice modes by circularly polarized light of opposite handedness. The excitation efficiencies of the lattice modes, and hence, the strength of the asymmetric transmission, are controlled by engineering the in-plane scattering of the individual plasmonic nanoparticles such that the maximum scattering imbalance occurs along one of the in-plane diffraction orders of the metasurface. Furthermore, we show that only the nonzero diffraction orders contribute to this effect. By highlighting the role of the localized plasmon modes supported by the nanoparticle and their radiative coupling to the lattice structure, our study provides a guideline for designing metasurfaces with asymmetric transmission enabled by lattice plasmons.