Anomalous transport of light at the phase transition to localization: strong dependence with incident angle

High ionic conductivity ceramics have potential technological applications in chemical sensors, ceramic permeable membranes, oxygen pumps, and solid oxide fuel cells. Recently ionic conductivity values as high as those of doped zirconia solid solutions have been found in a lanthanum molybdate compound. The high ionic conductivity of this compound, La2Mo2O9, is obtained at temperatures above the structural phase transition temperature (~580 °C). In this work the La2Mo2O9 ceramic material was prepared by the polymeric precursor technique and sintered at several dwell temperatures and soaking times to study the effect of sintering conditions on phase transition. It was found that there is a strong dependence of phase transition on the sintering profile. At 950 °C the phase transition is suppressed for short soaking times, whereas it is observed to occur for longer times. Moreover, the relative magnitude of conductivity is also dependent on the sintering conditions. The main conclusion is that the phase transition in La2Mo2O9 is particle sizedependent.

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Reflection Characteristics of Airy Beams Impinging on Graphene-Substrate Surfaces

International Journal of Optics ◽

10.1155/2022/5319174 ◽

2022 ◽

Vol 2022 ◽

pp. 1-10

Author(s):

Fuping Wu ◽

Yuanfei Hui ◽

Zhiwei Cui ◽

Ju Wang

Keyword(s):

Precise Measurement ◽

Incident Angle ◽

Strong Dependence ◽

Polarization State ◽

Potential Applications ◽

Beam Parameters ◽

Substrate Surfaces ◽

Analytical Expressions ◽

Reflection Characteristics ◽

Airy Beams

In this work, we analytically and numerically investigate the reflection characteristics of the airy beams impinging on graphene-substrate surfaces. The explicit analytical expressions for the electric and magnetic field components of the airy beams reflected from a graphene-substrate interface are derived. The local-field amplitude, Poynting vector, and spin and orbital angular momentum of the reflected airy beams with different graphene structure and beam parameters are presented and discussed. The results show that the reflection properties of the airy beams can be flexibly tuned by modulating the Fermi energy of the graphene and have a strong dependence on the incident angle and polarization state. These results may have potential applications in the modulation of airy beams and precise measurement of graphene structure parameters.

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A model to study finite-size and magnetic effects on the phase transition of a fermion interacting system

International Journal of Modern Physics B ◽

10.1142/s0217979218500911 ◽

2018 ◽

Vol 32 (08) ◽

pp. 1850091

Author(s):

Emerson B. S. Corrêa ◽

César A. Linhares ◽

Adolfo P. C. Malbouisson

Keyword(s):

Phase Transition ◽

Symmetry Breaking ◽

Order Phase Transition ◽

Chemical Potential ◽

Strong Dependence ◽

Finite Size ◽

Coupling Constants ◽

Magnetic Catalysis ◽

First Order Phase Transition ◽

Interacting Systems

We present a model to study the effects from external magnetic field, chemical potential and finite size on the phase structures of a massive four- and six-fermion interacting systems. These effects are introduced by a method of compactification of coordinates, a generalization of the standard Matsubara prescription. Through the compactification of the z-coordinate and of imaginary time, we describe a heated system with the shape of a film of thickness L, at temperature [Formula: see text] undergoing first- or second-order phase transition. We have found a strong dependence of the temperature transition on the coupling constants [Formula: see text] and [Formula: see text]. Besides inverse magnetic catalysis and symmetry breaking for both kinds of transition, we have found an inverse symmetry breaking phenomenon with respect to first-order phase transition.

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Anomalous transport properties ofNi2Mn1−xCrxGaHeusler alloys at the martensite-austenite phase transition

Physical Review B ◽

10.1103/physrevb.93.054419 ◽

2016 ◽

Vol 93 (5) ◽

Cited By ~ 17

Author(s):

Mahmud Khan ◽

Jeffrey Brock ◽

Ian Sugerman

Keyword(s):

Phase Transition ◽

Transport Properties ◽

Austenite Phase ◽

Anomalous Transport

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Synthesis, microstructure and effect of high pressures on transport properties of GdBaCo2O5,5

Transaction Kola Science Cetnre ◽

10.37614/2307-5252.2021.2.5.050 ◽

2021 ◽

Vol 12 (2-2021) ◽

pp. 247-252

Author(s):

T. N. Tarasenko ◽

◽

T. S. Sivachenko ◽

I. Yu. Reshidova ◽

V. V. Burkhovetskii ◽

...

Keyword(s):

Phase Transition ◽

Transition Temperature ◽

Hysteresis Loop ◽

High Pressures ◽

Strong Dependence ◽

Thermal Relaxation ◽

Temperature Hysteresis ◽

First Order ◽

M Phase ◽

Layered Cobaltite

In polycrystalline samples of double layered cobaltite GdBaCo2O5.5 the structure and resistivity at the first order “insulator-metal” (I-M) phase transition were studied at normal and high pressures. The strong dependence of the shape of the temperature hysteresis loop on the rate of temperature change indicates an infra-slow thermal relaxation of conductivity. Baric studies have shown an increase in the transition temperature ТIM at increasing pressure P with baric coefficient dТIM/dP ≈ 10 K/GPa. The spin blockade model is used to explain the observed effects.

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Contrast in Scanning Images of Thin Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095856 ◽

1972 ◽

Vol 30 ◽

pp. 520-521

Author(s):

S. Kimoto ◽

H. Hashimoto ◽

S. Takashima ◽

R. M. Stern ◽

T. Ichinokawa

Keyword(s):

Crystal Surface ◽

Solid Angle ◽

Incident Angle ◽

Intensity Variation ◽

Lattice Defects ◽

Scanning Microscope ◽

Electron Detector ◽

Backscattered Electrons ◽

Electron Image ◽

Backscattered Electron

The most well known application of the scanning microscope to the crystals is known as Coates pattern. The contrast of this image depends on the variation of the incident angle of the beam to the crystal surface. The defect in the crystal surface causes to make contrast in normal scanning image with constant incident angle. The intensity variation of the backscattered electrons in the scanning microscopy was calculated for the defect in the crystals by Clarke and Howie. Clarke also observed the defect using a scanning microscope.This paper reports the observation of lattice defects appears in thin crystals through backscattered, secondary and transmitted electron image. As a backscattered electron detector, a p-n junction detector of 0.9 π solid angle has been prepared for JSM-50A. The gain of the detector itself is 1.2 x 104 at 50 kV and the gain of additional AC amplifier using band width 100 Hz ∼ 10 kHz is 106.

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Microstructure of laser-irradiated, conducting Kapton polyimide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138889 ◽

1995 ◽

Vol 53 ◽

pp. 502-503

Author(s):

D. L. Callahan ◽

Z. Ball ◽

H. M. Phillips ◽

R. Sauerbrey

Keyword(s):

Electron Microscopy ◽

Phase Transition ◽

Transmission Electron Microscopy ◽

Cross Section ◽

Film Surface ◽

Cross Sectional ◽

General Utility ◽

Transmission Electron ◽

Considerable Debate ◽

Potential Applications

Ultraviolet laser-irradiation can be used to induce an insulator-to-conductor phase transition on the surface of Kapton polyimide. Such structures have potential applications as resistors or conductors for VLSI applications as well as general utility electrodes. Although the percolative nature of the phase transformation has been well-established, there has been little definitive work on the mechanism or extent of transformation. In particular, there has been considerable debate about whether or not the transition is primarily photothermal in nature, as we propose, or photochemical. In this study, cross-sectional optical microscopy and transmission electron microscopy are utilized to characterize the nature of microstructural changes associated with the laser-induced pyrolysis of polyimide.Laser-modified polyimide samples initially 12 μm thick were prepared in cross-section by standard ultramicrotomy. Resulting contraction in parallel to the film surface has led to distortions in apparent magnification. The scale bars shown are calibrated for the direction normal to the film surface only.

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The structure of membranes and membrane proteins embedded in amorphous ice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122563 ◽

1992 ◽

Vol 50 (1) ◽

pp. 432-433

Author(s):

Uwe Lücken ◽

Joachim Jäger

Keyword(s):

Phase Transition ◽

Transition Temperature ◽

Membrane Proteins ◽

Phase Transition Temperature ◽

Lipid Vesicles ◽

Freezing Stress ◽

Amorphous Ice ◽

Different Temperatures ◽

Band Pass ◽

Lipid Polymorphism

TEM imaging of frozen-hydrated lipid vesicles has been done by several groups Thermotrophic and lyotrophic polymorphism has been reported. By using image processing, computer simulation and tilt experiments, we tried to learn about the influence of freezing-stress and defocus artifacts on the lipid polymorphism and fine structure of the bilayer profile. We show integrated membrane proteins do modulate the bilayer structure and the morphology of the vesicles.Phase transitions of DMPC vesicles were visualized after freezing under equilibrium conditions at different temperatures in a controlled-environment vitrification system. Below the main phase transition temperature of 24°C (Fig. 1), vesicles show a facetted appearance due to the quasicrystalline areas. A gradual increase in temperature leads to melting processes with different morphology in the bilayer profile. Far above the phase transition temperature the bilayer profile is still present. In the band-pass-filtered images (Fig. 2) no significant change in the width of the bilayer profile is visible.

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