In this paper we investigate the effect of microstructure irregularities and applied strain on backward Brillouin scattering by comparing two photonic crystal fibers drawn with different parameters in order to minimize diameter and microstructure fluctuations. We fully characterize their Brillouin properties including the gain spectrum and the critical power. Using Brillouin echoes distributed ...

– We derive the transmission coefficient, T (ω), for grazing incidence of crystals with spatial dispersion accounting for the excitation of multiple modes with different wave vectors k for a given frequency ω. The generalization of the Fresnel formulas contains the refraction indices of these modes as determined by the dielectric function ǫ(ω,k). Near frequencies ωe, where the group velocity va...

The aim of this paper is to present the advantages of using Digital Image Correlation (DIC) and Infrared Thermography (IRT) to investigate the thermomechanical behavior of aluminum at the scale of its microstructure. The study combines these complementary imaging techniques: Electron Backscatter Diffraction (EBSD) to characterise the microstructure of the sample, DIC to obtain strain fields and...

A "crystal hotel" microfluidic device that allows crystal growth in confined volumes to be studied in situ is used to produce large calcite single crystals with predefined crystallographic orientation, microstructure, and shape by control of the detailed physical environment, flow, and surface chemistry. This general approach can be extended to form technologically important, nanopatterned sing...

A finite element based Monte Carlo procedure has been developed to predict the nominal elastic constants of thin films aggregates of anisotropic crystals. The geometry of the microstructure is approximated as a Johnson-Mehl tessellation. The statistical properties of the nominal Young’s modulus and Poisson’s ratio are expressed as functions of average number of grains within a unit volume and t...

we investigate the temperature-dependences of the Brillouin frequency shift in three different kind of single-mode fibers using a heterodyne method for sensing temperature. Positive dependences coefficients of 0.77, 0.56 and 1.45MHz/0C are demonstrated for 25 km long single-mode fiber, 10 km long non-zero dispersion shifted fiber and 100 m photonic crystal fiber, respectively. The results indic...

Historically, dry-snow metamorphism has been classified by the thermal environment and thermodynamic processes in a snowpack. Snow experiencing predominantly macroscopic isothermal conditions develops different microstructure than snow subjected to large temperature gradients. As such, much previous research has been categorized by and limited to specific thermal conditions. The current researc...

The present study endeavors to understand how small changes in the composition of cocoa butter affect its crystal habit, crystallization behavior, microstructure, and mechanical properties. Such compositional variations were attained by blending cocoa butter with 1 and 5% 1,2,3-tristearoyl-glycerol (SSS) or 1,2,3-trilinoleoyl-glycerol (LLL). Structural parameters such as crystallization kinetic...

Porous ZnGaNO microrods were synthesized by a single crystal internal decomposition route, and exhibited high performance in photoelectrochemical water splitting due to the high specific area and short charge transfer distance of the microstructure.