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Related papers: Nanostructure of edge dislocations in a smectic C*…

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Tubular crystals, two-dimensional lattices wrapped into cylindrical topologies, arise in many contexts, including botany and biofilaments, and in physical systems such as carbon nanotubes. The geometrical principles of botanical…

Soft Condensed Matter · Physics 2016-10-05 Daniel A. Beller , David R. Nelson

We study the structure of very thin liquid crystal films frustrated by antagonistic anchorings in the smectic phase. In a cylindrical geometry, the structure is dominated by the defects for film thicknesses smaller than 150 nm and the…

Disclinations or disclination clusters in smectic C freely suspended films with topological charges larger than one are unstable. They disintegrate, preferably in a spatially symmetric fashion, into single defects with individual charges…

Soft Condensed Matter · Physics 2023-07-28 Ralf Stannarius , Kirsten Harth

Plasticity in hexagonal close-packed zirconium is mainly controlled by the glide of dislocations with 1/3<1-210> Burgers vectors. As these dislocations cannot accommodate deformation in the [0001] direction , twinning or glide of <c+a>…

Materials Science · Physics 2020-09-07 Thomas Soyez , Daniel Caillard , Fabien Onimus , Emmanuel Clouet

Smectic liquid crystals can be viewed as model systems for lamellar structures for which there has been extensive theoretical development. We demonstrate that a nonlinear energy description is required with respect to the usual Landau-de…

Large-scale atomistic calculations, using empirical potentials for modeling semiconductors, have been performed on a stressed system with linear surface defects like steps. Although the elastic limits of systems with surface defects remain…

Materials Science · Physics 2007-09-12 Julien Godet , Laurent Pizzagalli , Sandrine Brochard , Pierre Beauchamp

Quasicrystals (QCs) are a class of aperiodic ordered structures that emerge in various systems, from metallic alloys to soft matter and driven non-equilibrium systems. Within a mesoscale theory based on slowly-varying complex amplitudes for…

Materials Science · Physics 2025-09-12 Marcello De Donno , Luiza Angheluta , Marco Salvalaglio

We explore the structure and magnetic field response of edge dislocations in Grandjean-Cano wedge cells filled with chiral mixtures of the ferroelectric nematic mesogen DIO. Upon cooling, the ordering changes from paraelectric in the…

Using first principles methods we calculated the entire {\gamma}-surface of the first order pyramidal planes in {\alpha}-titanium. Slip on these planes involving dislocations with c + a dislocations is one means by which {\alpha}-titanium…

Materials Science · Physics 2016-10-04 Adam J. Ready , Adrian P. Sutton , Peter D. Haynes , David Rugg

Smectic order on arbitrary curved substrate can be described by a differential form of rank one (1-form), whose geometric meaning is the differential of the local phase field of the density modulation. The exterior derivative of 1-form is…

Soft Condensed Matter · Physics 2009-11-13 Xiangjun Xing

A discrete model describing defects in crystal lattices and having the standard linear anisotropic elasticity as its continuum limit is proposed. The main ingredients entering the model are the elastic stiffness constants of the material…

Materials Science · Physics 2007-05-23 A. Carpio , L. L. Bonilla

This work unravels the atomic details of the interaction of solute atoms with nanoscale crystalline defects. The complexity of this phenomenon is elucidated through detailed atom probe tomographic investigations on epitaxially-strained,…

Materials Science · Physics 2021-12-22 Samik Mukherjee , Simone Assali , Oussama Moutanabbir

We provide a minimal continuum model for mesoscale plasticity, explaining the cellular dislocation structures observed in deformed crystals. Our dislocation density tensor evolves from random, smooth initial conditions to form self-similar…

Materials Science · Physics 2010-09-03 Yong S. Chen , Woosong Choi , Stefanos Papanikolaou , James P. Sethna

The phase-field crystal model in its amplitude equation approximation is shown to provide an accurate description of the deformation field in defected crystalline structures, as well as of dislocation motion. We analyze in detail the…

Materials Science · Physics 2020-01-01 Marco Salvalaglio , Luiza Angheluta , Zhi-Feng Huang , Axel Voigt , Ken R. Elder , Jorge Viñals

In our previous study, we demonstrated the existence of an unidentified ferroelectric smectic phase in the low-temperature region of the ferroelectric smectic A phase, where the layer spacing decreases with decreasing temperature. In the…

Tetradymite-structured chalcogenides such as bismuth telluride Bi_{2}Te_{3} are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of…

Materials Science · Physics 2019-04-25 D. L. Medlin , N. Yang , C. D. Spataru , L. M. Hale , Y. Mishin

Liquid crystalline systems exhibiting both macroscopic chirality and smectic order experience frustration resulting in mesophases possessing complex three-dimensional order. In the twist-grain-boundary phase, defect lattices mediate the…

Soft Condensed Matter · Physics 2009-12-18 Elisabetta A. Matsumoto , Gareth P. Alexander , Randall D. Kamien

In this paper we consider the dynamics of dislocations with the same Burgers vector, contained in the same glide plane, and moving in a material with periodic obstacles. We study two cases: i) the particular case of parallel straight…

Analysis of PDEs · Mathematics 2015-05-13 A. El Hajj , H. Ibrahim , R. Monneau

Rod-like objects at high packing fractions can form smectic phases, where the rods break rotational and translational symmetry by forming lamellae. Smectic defects thereby include both discontinuities in the rod orientational order…

Soft Condensed Matter · Physics 2023-12-01 Ethan I. L. Jull , Gerardo Campos-Villalobos , Qianjing Tang , Marjolein Dijkstra , Lisa Tran

Following Nye and Berry's analogy with crystal dislocations, an approach to the Burgers vector of a wave dislocation (phase singularity, optical vortex) is proposed. It is defined to be a regularized phase gradient evaluated at the phase…

Optics · Physics 2010-05-31 Mark R. Dennis