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Related papers: Nematic--to--Smectic-A Transition in Aerogel

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Modeling and simulation studies using a high-order Landau-de Gennes type model for the direct isotropic/smectic-A liquid crystal transition are presented showing the existence of meta-stable nematic pre-ordering under certain conditions, in…

Soft Condensed Matter · Physics 2009-06-29 Nasser Mohieddin Abukhdeir , Alejandro D. Rey

High resolution measurements reveal that condensation isotherms of $^4$He in a silica aerogel become discontinuous below a critical temperature. We show that this behaviour does not correspond to an equilibrium phase transition modified by…

Disordered Systems and Neural Networks · Physics 2014-09-09 Geoffroy Aubry , Fabien Bonnet , Mathieu Melich , Laurent Guyon , Panayotis Spathis , Florence Despetis , Pierre-Etienne Wolf

A review is given on the theory of vortex-glass phases in impure type-II superconductors in an external field. We begin with a brief discussion of the effects of thermal fluctuations on the spontaneously broken U(1) and translation…

Superconductivity · Physics 2015-06-24 T. Nattermann , S. Scheidl

The emergence of nematic order on deformable closed surfaces plays a pivotal role in the morphogenesis of active biological matter, such as the regeneration of Hydra. In this work, we present a continuum model that couples the…

Soft Condensed Matter · Physics 2026-03-10 Gaetano Napoli , Silvia Paparini

We study the kinetics of the nematic-isotropic transition in a two-dimensional liquid crystal by using a lattice Boltzmann scheme that couples the tensor order parameter and the flow consistently. Unlike in previous studies, we find the…

Soft Condensed Matter · Physics 2009-11-07 Colin Denniston , Enzo Orlandini , J. M. Yeomans

In this paper we consider a recent experiment [Kang et al. PRA 95 053638 (2017)] in which an antiferromagnetic spin-1 condensate of 23Na atoms was quenched from the easy-axis polar phase into the easy-plane polar phase. We simulate the…

Quantum Gases · Physics 2018-12-19 L. M. Symes , D. Baillie , P. B. Blakie

We directly image individual vortex positions in nanocrystals in order to unveil the structural property that contributes to the depletion of the entropy-jump entailed at the first-order transition. On reducing the nanocrystal size the…

An extension to a high-order model for the direct isotropic/smectic-A liquid crystalline phase transition was derived to take into account thermal effects including anisotropic thermal diffusion and latent heat of phase-ordering.…

Soft Condensed Matter · Physics 2009-09-29 Nasser Mohieddin Abukhdeir , Alejandro D. Rey

We study periodic lattices, such as vortex lattices in type II superconductors in a random pinning potential. For the static case we review the prediction that the phase diagram of such systems consists of a topologically ordered Bragg…

Superconductivity · Physics 2016-08-31 T. Giamarchi , P. Le Doussal

Mixed surfactant systems with strongly bound counterions show many interesting phases such as the random mesh phase consisting of a disordered array of defects (water-filled nano-pores in the bilayers). The present study addresses the…

Soft Condensed Matter · Physics 2021-07-13 Pradip K. Bera , Vikram Rathee , Rema Krishnaswamy , A. K. Sood

We numerically study a disordered model for the RNA secondary structure and we find that it undergoes a phase transition, with a breaking of the replica symmetry in the low temperature region (like in spin glasses). Our results are based on…

Disordered Systems and Neural Networks · Physics 2009-10-31 A. Pagnani , G. Parisi , F. Ricci-Tersenghi

In this paper we study the 3d frustrated lattice gas model in the annealed version, where the disorder is allowed to evolve in time with a suitable kinetic constraint. Although the model does not exhibit any thermodynamic transition it…

Disordered Systems and Neural Networks · Physics 2009-10-31 Annalisa Fierro , Antonio de Candia , Antonio Coniglio

We present Monte Carlo simulations of a dense polymer melt which shows glass-transition-like slowing-down upon cooling, as well as a build up of nematic order. At small wave vectors q this model system shows excess scattering similar to…

Statistical Mechanics · Physics 2009-10-28 H. Weber , W. Paul , W. Kob , K. Binder

We mathematically model Smectic-A (SmA) phases with a modified Landau-de Gennes (mLdG) model. The orientational order of the SmA phase is described by a tensor-order parameter $\mathbf{Q}$, and the positional order is described by a real…

Soft Condensed Matter · Physics 2025-09-22 Baoming Shi , Yucen Han , Chengdi Ma , Apala Majumdar , Lei Zhang

We explore the smectic liquid crystal order in a cell with a "dirty" substrate imposing random pinnings. Within harmonic elasticity we find a subtle three-dimensional surface disorder-driven transition into a pinned smectic-glass,…

Soft Condensed Matter · Physics 2012-06-14 Quan Zhang , Leo Radzihovsky

We find in a model system of thermotropic liquid crystals that the translational diffusion coefficient parallel to the director $D_{\parallel}$ first increases and then decreases as temperature drops through the nematic phase, and this…

Soft Condensed Matter · Physics 2009-11-11 Dwaipayan Chakrabarti , Biman Bagchi

We use lattice Boltzmann simulations of the Beris--Edwards formulation of nematodynamics to probe the response of a nematic liquid crystal with conflicting anchoring at the boundaries under shear and Poiseuille flow. The geometry we focus…

Soft Condensed Matter · Physics 2009-11-10 D. Marenduzzo , E. Orlandini , J. M. Yeomans

Although crystals are usually quite stable, they are sensitive to a disordered environment: even an infinitesimal amount of impurities can lead to the destruction of the crystalline order. The resulting state of matter has been a…

Superconductivity · Physics 2009-11-07 T. Klein , I. Joumard , S. Blanchard , J. Marcus , R. Cubitt , T. Giamarchi , P. Le Doussal

Anisotropic aerogel possesses structure which exhibits a strong influence over the composition and orientation of the order parameter of imbibed superfluid $^3$He. Computational studies have identified stretched aerogel with plane-like…

Superconductivity · Physics 2024-03-01 J. W. Scott , M. D. Nguyen , D. Park , W. P. Halperin

In equilibrium, disorder conspires with topological defects to redefine the ordered states of matter in systems as diverse as crystals, superconductors and liquid crystals. Far from equilibrium, however, the consequences of quenched…

Soft Condensed Matter · Physics 2021-03-09 Amélie Chardac , Suraj Shankar , M. Cristina Marchetti , Denis Bartolo