Structural and Magnetic Characterization of Large Area, Free-Standing Thin Films of Magnetic Ion Intercalated Dichalcogenides Mn0.25TaS2 and Fe0.25TaS2

Free-standing thin films of magnetic ion intercalated transition metal dichalcogenides are produced using ultramicrotoming techniques. Films of thicknesses ranging from 30nm to 250nm were achieved and characterized using transmission electron diffraction and X-ray magnetic circular dichroism. Diffraction measurements visualize the long range crystallographic ordering of the intercalated ions, while the dichroism measurements directly assess the orbital contributions to the total magnetic moment. We thus verify the unquenched orbital moment in Fe0.25TaS2 and measure the fully quenched orbital contribution in Mn0.25TaS2. Such films can be used in a wide variety of ultrafast X-ray and electron techniques that benefit from transmission geometries, and allow measurements of ultrafast structural, electronic, and magnetization dynamics in space and time

Second harmonic generation from thin slabs in the discrete dipole approach

The nonlinear optical response of thin Si slabs is calculated using a discrete dipole approach. The s-polarized second harmonic response as a function of the angle of incidence appears to be in reasonable agreement with experimental results. The p-polarized SHG shows a high sensitivity for the shape of the polarizability profile

Probing the coupled adhesion and deformation characteristics of suspension cells

published_or_final_versio

Resolving the order parameter of High-Tc_{c} Superconductors through quantum pumping spectroscopy

The order parameter of High-T$_{c}$ superconductors through a series of experiments has been quite conclusively demonstrated to not be of the normal $s-wave$ type. It is either a pure $d_{x^{2}-y^{2}}$-wave type or a mixture of a $d_{x^{2}-y^{2}}-wave$ with a small imaginary $s-wave$ or $d_{xy}-wave$ component. In this work a distinction is brought out among the four types, i.e., $s- wave$, $d_{x^{2}-y^{2}}- wave$, $d_{x^{2}-y^{2}}+is - wave$ and $d_{x^{2}-y^{2}}+id_{xy}- wave$ types with the help of quantum pumping spectroscopy. This involves a normal metal double barrier structure in contact with a High-T$_{c}$ superconductor. The pumped current, heat and noise show different characteristics with change in order parameter revealing quite easily the differences among these.Comment: 11 pages, 3 figures, 1 table, Manuscript revised with new material on d+id' cas

Crack detection using enhanced thresholding on UAV based collected images

© 2018 Australasian Robotics and Automation Association. All rights reserved. This paper proposes a thresholding approach for crack detection in an unmanned aerial vehicle (UAV) based infrastructure inspection system. The proposed algorithm performs recursively on the intensity histogram of UAV-taken images to exploit their crack-pixels appearing at the low intensity interval. A quantified criterion of interclass contrast is proposed and employed as an object cost and stop condition for the recursive process. Experiments on different datasets show that our algorithm outperforms different segmentation approaches to accurately extract crack features of some commercial buildings

Flux distribution at the cross section of stacked nanostructured magnetic ribbon

Conventional magnetization methods only measure the average magnetic properties over the whole sample. The information is insufficient to understand the local character. This paper presents the visualized magnetization process and its profiles in detail at the cross section of the FINEMET ribbon using advanced magnetooptical imaging technique. External magnetic fields were applied parallel to the surface of the ribbon. A magnetization curve was plotted by interpreting the profile of intensity of magnetooptical images. The profile indicates that the flux densities are higher at the cross section of the ribbons compared with those at the gaps between the ribbons. The flux lines mainly transmit inside the FINEMET ribbons though there are some stray fields between the ribbons. © 2009 IEEE

"Optical conductance fluctuations: diagrammatic analysis in Landauer approach and non-universal effects"

The optical conductance of a multiple scattering medium is the total transmitted light of a diffuse incoming beam. This quantity, very analogous to the electronic conductance, exhibits universal conductance fluctuations. We perform a detailed diagrammatic analysis of these fluctuations. With a Kadanoff-Baym technique all the leading diagrams are systematically generated. A cancellation of the short distance divergencies occurs, that yields a well behaved theory. The analytical form of the fluctuations is calculated and applied to optical systems. Absorption and internal reflections reduce the fluctuations significantly.Comment: 25 pages Revtex 3.0, 18 seperate postscript figure

ρ\rho-mass Modification in He3He^3 - a Signal of Restoration of Chiral Symmetry or Test for Nuclear Matter Models ?

Two recent experiments have demonstrated that the effective $\rho$-mass in nuclear medium, as extracted from the $^3He(\gamma, \pi^+ \pi^-)$ reaction, is substantially reduced. This has been advocated as an indication of partial restoration of chiral symmetry in nuclear matter. We show that even in the absence of chiral symmetry, effective mean field nuclear matter models can explain these findings quantitatively.Comment: ReVTeX file with 2 postscript figures include

Non-collinear magnetic structure and anisotropic magnetoelastic coupling in cobalt pyrovanadate Co2V2O7

The Co2V2O7 is recently reported to exhibit amazing magnetic field-induced magnetization plateaus and ferroelectricity, but its magnetic ground state remains ambiguous due to its structural complexity. Magnetometry measurements, and time-of-flight neutron powder diffraction (NPD) have been employed to study the structural and magnetic properties of Co2V2O7, which consists of two non-equivalent Co sites. Upon cooling below the Ne\'el temperature TN = 6.3 K, we observe magnetic Bragg peaks at 2K in NPD which indicated the formation of long range magnetic order of Co2+ moments. After symmetry analysis and magnetic structure refinement, we demonstrate that Co2V2O7 possesses a complicated non-collinear magnetic ground state with Co moments mainly located in b-c plane and forming a non-collinear spin-chain-like structure along the c-axis. The ab initio calculations demonstrate that the non-collinear magnetic structure is more stable than various ferromagnetic states at low temperature. The non-collinear magnetic structure with canted up-up-down-down spin configuration is considered as the origin of magnetoelectric coupling in Co2V2O7 because the inequivalent exchange striction induced by the spin-exchange interaction between the neighboring spins is the driving force of ferroelectricity. Besides, it is found that the deviation of lattice parameters a and b is opposite below TN, while the lattice parameter c and stay almost constant below TN, evidencing the anisotropic magnetoelastic coupling in Co2V2O7.Comment: 9 pages, 8 figure