English
Related papers

Related papers: Crystallography, Lorentz violation, and the Standa…

200 papers

The modified Dirac equation in the Lorentz-violating Standard-Model Extension (SME) is considered. Within this framework, the construction of a hermitian Hamiltonian to all orders in the Lorentz-breaking parameters is investigated, discrete…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ralf Lehnert

We review our recent Michelson-Morley (MM) and Kennedy-Thorndike (KT) experiment, which tests Lorentz invariance in the photon sector, and report first results of our ongoing atomic clock test of Lorentz invariance in the matter sector. The…

Optical properties of materials related to light absorption and scattering are explained by the excitation of electrons. The Bethe-Salpeter equation is the state-of-the-art approach to describe these processes from first principles (ab…

Numerical Analysis · Mathematics 2020-08-21 Peter Benner , Carolin Penke

We present the first results from a rotating Michelson-Morley experiment that uses two orthogonally orientated cryogenic sapphire resonator-oscillators operating in whispering gallery modes near 10 GHz. The experiment is used to test for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paul L. Stanwix , Michael E. Tobar , Peter Wolf , Mohamad Susli , Clayton R. Locke , Eugene N. Ivanov , John Winterflood , Frank van Kann

We develop a relativistic variational model for a nematic liquid crystal interacting with an electro- magnetic field. The constitutive relation for a general anisotropic uniaxial diamagnetic and dielectric medium is analyzed. We discuss…

Classical Physics · Physics 2012-09-21 Yuri N. Obukhov , Tomas Ramos , Guillermo F. Rubilar

The recently developed information-theoretic approach to crystallographic symmetry classifications and quantifications in two dimensions (2D) from digital transmission electron and scanning probe microscope images is adapted for the…

Materials Science · Physics 2022-02-15 Peter Moeck , Lukas von Koch

Molecular and polymeric crystals show a wide range of functional properties that arise from the interplay between the atomic-scale structure of their constituent molecules and the organization of these molecules within the crystal lattice…

The precise crystal symmetry and hence the emergence of the electric polarization still remains an open question in the multiferroic materials $R$Mn$_2$O$_5$ ($R$ = rare-earth, Bi, Y). While previous diffraction studies have indicated that…

Strongly Correlated Electrons · Physics 2022-06-22 N. Narayanan , P. J. Graham , P. Rovillain , J. O'Brien , J. Bertinshaw , S. Yick , J. Hester , A. Maljuk , D. Souptel , B. Büchner , D. Argyriou , C. Ulrich

Understanding of the intimate cross-coupling between electric and magnetic degrees of freedom in solids usually requires sophisticated models and time-consuming calculation methods. Instead of macroscopic symmetry analysis, we present a…

Materials Science · Physics 2022-02-02 Maocai Pi , Xifan Xu , Mingquan He , Yisheng Chai

In this article the mechanism of the linear magnetoelectric (ME) effect in the rhombohedral multiferroic BiFeO$_3$ is considered. The study is based on the symmetry approach of the GinzburgLandau type, in which polarization,…

Materials Science · Physics 2016-04-06 A. F. Popkov , M. D. Davydova , K. A. Zvezdin , S. V. Solov'yov , A. K. Zvezdin

Here we discuss the standard model extension in the presence of CPT-odd Lorentz violation (LV) sector and of a deformed Heisenberg algebra that leads to a non-commutative theory with minimum length (ML). We derive the set of Maxwell…

General Physics · Physics 2017-06-16 T. Prudencio , H. Belich , H. L. C. Louzada

Four-dimensional scanning transmission electron microscopy (4D-STEM) provides rich, atomic-scale insights into materials structures. However, extracting specific physical properties - such as polarization directions essential for…

Strong field photoemission and electron recollision provide a viable route to extract electronic and nuclear dynamics from molecular targets with attosecond temporal resolution. However, since an {\em ab-initio} treatment of even the…

Atomic Physics · Physics 2016-11-02 N. Suárez , A. Chacón , M. F. Ciappina , B. Wolter , J. Biegert , M. Lewenstein

A new theory is developed for the magnetoelectric (ME) coupling in a symmetric 2-2 ME laminate having a representative piezoelectric crystal (PMN-PT) particularly with anisotropic piezoelectric properties. Considering the average field…

The robust and automated determination of crystal symmetry is of utmost importance in material characterization and analysis. Recent studies have shown that deep learning (DL) methods can effectively reveal the correlations between X-ray or…

Computational Physics · Physics 2020-05-27 Leslie Ching Ow Tiong , Jeongrae Kim , Sang Soo Han , Donghun Kim

In this work we consider the Landau-de Gennes model for liquid crystals with an external electromagnetic field to model the occurrence of the saturn ring effect under the assumption of rotational equivariance. After a rescaling of the…

Analysis of PDEs · Mathematics 2021-07-28 François Alouges , Antonin Chambolle , Dominik Stantejsky

In the recent times, test of Lorentz Invariance has been used as a means to probe theories of physics beyond the standard model. We describe a simple way of utilizing the polarimeters, which are a critical beam instrument at precision and…

Nuclear Experiment · Physics 2016-01-13 Prajwal Mohanmurthy , Dipangkar Dutta , Amrendra Narayan

Smectic liquid crystals are remarkable, beautiful examples of materials microstructure, with ordered patterns of geometrically perfect ellipses and hyperbolas. The solution of the complex problem of filling three-dimensional space with…

Soft Condensed Matter · Physics 2016-04-08 Danilo B. Liarte , Matthew Bierbaum , Ricardo A. Mosna , Randall D. Kamien , James P. Sethna

Complex Band Structures and Multiple Scattering Theory have been used in this paper to analyze the overlapping of the evanescent waves localized in point defects in Sonic Crystals. The Extended Plane Wave Expansion (EPWE) with supercell…

Materials Science · Physics 2012-08-27 V. Romero-García , J. V. Sánchez-Pérez , and L. M. Garcia-Raffi

We compare the Lorentz violation terms of the pure photon sector between two field theory models, namely the minimal standard model extension (SME) and the standard model supplement (SMS). From the requirement of the identity of the…

High Energy Physics - Phenomenology · Physics 2014-08-27 Zhou Lingli , Bo-Qiang Ma