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Related papers: Casimir stresses in active nematic films

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Casimir forces between material surfaces at close proximity of less than 200 nm can lead to increased chaotic behavior of actuating devices depending on the strength of the Casimir interaction. We investigate these phenomena for phase…

Applied Physics · Physics 2017-11-01 Fatemeh Tajik , Mehdi Sedigh , Mohammad Khorrami , Amir Ali Masoudi , George Palasantzas

We study Casimir interactions between cylinders in thermal non-equilibrium, where the objects as well as the environment are held at different temperatures. We provide the general formula for the force, in a one reflection approximation,…

Quantum Physics · Physics 2013-01-17 Vladyslav A. Golyk , Matthias Krüger , M. T. Homer Reid , Mehran Kardar

In this letter we consider the fluctuation induced force exerted between two plates separated by a distance $L$ in a fluid with a temperature gradient. We predict that, for a range of distances $L$, this non-equilibrium force is anomalously…

Statistical Mechanics · Physics 2013-06-13 T. R. Kirkpatrick , J. M. Ortiz de Zárate , J. V. Sengers

There is a recent interest in studying odd elasticity in soft solids. Current focus has been on simple solids. However, many soft solids are structured and can exhibit nematic elasticity or viscoelasticity. Here we generalize the concept of…

Soft Condensed Matter · Physics 2026-03-19 Zeyang Mou , Haijie Ren , Ding Xu , Igor S. Aranson , Rui Zhang

When masless excitations are limited or modified by the presence of material bodies one observes a force atcing between them generally called Casimir force. Such excitations are present in any fluid system close to its true bulk critical…

Statistical Mechanics · Physics 2016-04-27 Daniel M. Dantchev , Vassil M. Vassilev , Peter A. Djondjorov

Liquid crystal elastomers are cross-linked elastomer networks with liquid crystal mesogens incorporated into the main or side chain. Polydomain liquid crystalline (nematic) elastomers exhibit unusual mechanical properties like soft…

Soft Condensed Matter · Physics 2024-05-21 Ameneh Maghsoodi , Kaushik Bhattacharya

Recent experiments have measured the critical Casimir force acting on a colloid immersed in a binary liquid mixture near its continuous demixing phase transition and exposed to a chemically structured substrate. Motivated by these…

Statistical Mechanics · Physics 2013-11-27 Francesco Parisen Toldin , Matthias Tröndle , S. Dietrich

he Casimir force is calculated between plates with thin metallic coating. Thin films are described with spatially dispersive (nonlocal) dielectric functions. For thin films the nonlocal effects are more relevant than for half-spaces.…

Quantum Physics · Physics 2007-05-23 R. Esquivel , V. Svetovoy

We consider a continuum model of active viscoelastic matter, whereby an active nematic liquid-crystal is coupled to a minimal model of polymer dynamics with a viscoelastic relaxation time $\tau_C$. To explore the resulting interplay between…

Soft Condensed Matter · Physics 2016-03-30 E. J. Hemingway , M. E. Cates , S. M. Fielding

We use linear stability analysis to show that an isotropic phase of elongated particles with dipolar flow fields can develop nematic order as a result of their activity. We argue that ordering is favoured if the particles are flow-aligning…

Soft Condensed Matter · Physics 2020-03-18 Sreejith Santhosh , Mehrana R. Nejad , Amin Doostmohammadi , Julia M. Yeomans , Sumesh P. Thampi

If a fluctuating medium is confined, the ensuing perturbation of its fluctuation spectrum generates Casimir-like effective forces acting on its confining surfaces. Near a continuous phase transition of such a medium the corresponding order…

Soft Condensed Matter · Physics 2011-02-15 A. Gambassi , A. Maciolek , C. Hertlein , U. Nellen , L. Helden , C. Bechinger , S. Dietrich

A body immersed in a nematic liquid crystal disturbs the fluid's preferred molecular configuration and increases its stored elastic energy. In an active nematic, the fluid components also generate a stress in the bulk fluid. By introducing…

Soft Condensed Matter · Physics 2025-06-17 Thomas G. J. Chandler , Saverio E. Spagnolie

Stability is an important and fruitful avenue of research for liquid crystal elastomers. At constant temperature, upon stretching, the homogeneous state of a nematic body becomes unstable, and alternating shear stripes develop at very low…

Soft Condensed Matter · Physics 2021-05-17 L. Angela Mihai , Alain Goriely

We present both analytical and numerical results for the behaviour of the Casimir force in a Ginzburg-Landau type model of a film of a simple fluid or binary liquid mixture in which the confining surfaces are strongly adsorbing but…

Statistical Mechanics · Physics 2018-11-06 Daniel Dantchev , Vassil Vassilev , Peter Djondjorov

Wet active matter in the presence of an imposed temperature gradient, or chemical potential gradient, is considered. It is shown that there is a new type of convective instability that is caused by a (negative) activity parameter.…

Soft Condensed Matter · Physics 2019-02-15 T. R. Kirkpatrick , J. K. Bhattacherjee

We want to study the dynamics of a simple linear harmonic micro spring which is under the influence of the quantum Casimir force/pressure and thus behaves as a (an) nonlinear (anharmonic) Casimir oscillator. Generally,the equation of motion…

Quantum Physics · Physics 2014-03-14 Habibollah Razmi , Mohammad Reza Mohammadi , Mahnaz Abdollahi , Seyed Mahdi Fazeli

We discuss instabilities of fluid films of nanoscale thickness, with a particular focus on films where the destabilising mechanism allows for linear instability, metastability, and absolute stability. Our study is motivated by nematic…

Soft Condensed Matter · Physics 2018-04-04 Michael-Angelo Y. -H. Lam , Linda J. Cummings , Lou Kondic

A paradigm for internally driven matter is the active nematic liquid crystal, whereby the equations of a conventional nematic are supplemented by a minimal active stress that violates time reversal symmetry. In practice, active fluids may…

Soft Condensed Matter · Physics 2015-12-15 E. J. Hemingway , A. Maitra , S. Banerjee , M. C. Marchetti , S. Ramaswamy , S. M. Fielding , M. E. Cates

We calculate the effective forces on hard disks near walls embedded inside active nematic liquid crystals. When the disks are sufficiently close to the wall and the flows are sufficiently slow, we can obtain exact expressions for the…

Soft Condensed Matter · Physics 2024-06-07 Luke Neville , Jens Eggers , Tanniemola Liverpool

The hydrodynamic stresses created by active particles can destabilise orientational order present in the system. This is manifested, for example, by the appearance of a bend instability in active nematics or in quasi-2-dimensional living…

Soft Condensed Matter · Physics 2024-06-05 Bhavesh Gautam , Juho Lintuvuori