History-Dependent Patterns in Randomly Perturbed Nematic Liquid Crystals

We study the characteristics of nematic structures in a randomly perturbed nematic liquid crystal (LC) phase. We focus on the impact of the samples history on the universal behavior. The obtained results are of interest for every randomly perturbed system exhibiting a continuous symmetry-breaking phase transition. A semimicroscopic lattice simulation is used where the LC molecules are treated as cylindrically symmetric, rod-like objects interacting via a Lebwohl-Lasher (LL) interaction. Pure LC systems exhibit a first order phase transition into the orientationally ordered nematic phase atT=Tcon lowering the temperatureT. The orientational ordering of LC molecules is perturbed by the quenched, randomly distributed rod-likeimpuritiesof concentrationp. Their orientation is randomly distributed, and they are coupled with the LC molecules via an LL-type interaction. Only concentrations below the percolation threshold are considered. The key macroscopic characteristics of perturbed LC structures in the symmetry-broken nematic phase are analyzed for two qualitatively different histories atT≪Tc. We demonstrate that, for a weak enough interaction among the LC molecules andimpurities, qualitatively different history-dependent states could be obtained. These states could exhibit either short-range, quasi-long-range, or even long-range order.

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Thermodynamic properties of a spin-1 model with long-range interactions

Modern Physics Letters B ◽

10.1142/s0217984918500537 ◽

2018 ◽

Vol 32 (05) ◽

pp. 1850053 ◽

Cited By ~ 5

Author(s):

Ji-Xuan Hou ◽

Xu-Chen Yu

Keyword(s):

Magnetic Field ◽

Phase Transition ◽

Phase Diagram ◽

Long Range ◽

Order Phase Transition ◽

First Order ◽

First Order Phase Transition ◽

Long Range Interactions ◽

External Magnetic Field Strength ◽

First Order Phase

The long-range interacting spin-1 chain placed in a staggered magnetic field is studied by means of microcanonical approach. Firstly, we study the microcanonical entropy of the system in the thermodynamic limit and find the system is non-ergodic and can exhibit either first-order phase transition or second-order phase transition by shifting the external magnetic field strength. Secondly, we construct the global phase diagram of the system and find a phase transition area in the phase diagram corresponding to the temperature jump of the first-order phase transition.

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LONG RANGE ORDER IN THE BLUME-EMERY-GRIFFITHS MODEL

Modern Physics Letters B ◽

10.1142/s021798499100188x ◽

1991 ◽

Vol 05 (23) ◽

pp. 1583-1590

Author(s):

M. CORGINI

Keyword(s):

Phase Transition ◽

Long Range ◽

Order Phase Transition ◽

Range Order ◽

Long Range Order ◽

First Order ◽

First Order Phase Transition ◽

Infrared Bounds ◽

First Order Phase

Using the Infrared Bounds method it ws demonstrated that a first order phase transition takes place in the m-dimensional (m≥3) Blume-Emery-Griffiths model.

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Invasion percolation with long-range correlations: First-order phase transition and nonuniversal scaling properties

Physical Review E ◽

10.1103/physreve.61.4920 ◽

2000 ◽

Vol 61 (5) ◽

pp. 4920-4934 ◽

Cited By ~ 58

Author(s):

Mark A. Knackstedt ◽

Muhammad Sahimi ◽

Adrian P. Sheppard

Keyword(s):

Phase Transition ◽

Long Range ◽

Order Phase Transition ◽

Invasion Percolation ◽

Scaling Properties ◽

Long Range Correlations ◽

First Order ◽

First Order Phase Transition ◽

First Order Phase

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Thermodynamic analysis of a long-range interacting spin system

Modern Physics Letters B ◽

10.1142/s0217984919500726 ◽

2019 ◽

Vol 33 (07) ◽

pp. 1950072 ◽

Cited By ~ 2

Author(s):

Zhen-Yu Yang ◽

Ji-Xuan Hou

Keyword(s):

Phase Transition ◽

Long Range ◽

Order Phase Transition ◽

First Order ◽

Negative Specific Heat ◽

Temperature Jumps ◽

First Order Phase Transition ◽

Canonical Approach ◽

First Order Phase ◽

Second Order Phase Transition

A long-range interacting Fermi chain placed in the uniform and the staggered magnetic field is studied via the micro-canonical approach. The relation between the entropy and the energy of the system is obtained by counting the number of microscopic states. We find that this system is non-ergodic and can exhibit first-order phase transition, second-order phase transition, or both. The microcanonical ensemble predicts negative specific heat regions and temperature jumps. Moreover, the global phase diagram of the system is constructed.

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Surface ordering and destruction of the first order phase transition smectic A-smectic C* in free standing smectic films

Journal de Physique II ◽

10.1051/jp2:1994237 ◽

1994 ◽

Vol 4 (10) ◽

pp. 1865-1874 ◽

Cited By ~ 10

Author(s):

E. Demikhov ◽

U. Hoffmann ◽

H. Stegemeyer

Keyword(s):

Phase Transition ◽

Order Phase Transition ◽

Free Standing ◽

First Order ◽

Surface Ordering ◽

Smectic A ◽

Smectic C ◽

First Order Phase Transition ◽

First Order Phase

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Gravitational wave signals of dark matter freeze-out

Journal of High Energy Physics ◽

10.1007/jhep02(2021)022 ◽

2021 ◽

Vol 2021 (2) ◽

Cited By ~ 3

Author(s):

Danny Marfatia ◽

Po-Yan Tseng

Keyword(s):

Phase Transition ◽

Dark Matter ◽

Gravitational Waves ◽

Order Phase Transition ◽

First Order ◽

Stochastic Background ◽

First Order Phase Transition ◽

Relic Abundance ◽

First Order Phase ◽

Freeze Out

Abstract We study the stochastic background of gravitational waves which accompany the sudden freeze-out of dark matter triggered by a cosmological first order phase transition that endows dark matter with mass. We consider models that produce the measured dark matter relic abundance via (1) bubble filtering, and (2) inflation and reheating, and show that gravitational waves from these mechanisms are detectable at future interferometers.

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Dark Matter production from relativistic bubble walls

Journal of High Energy Physics ◽

10.1007/jhep03(2021)288 ◽

2021 ◽

Vol 2021 (3) ◽

Author(s):

Aleksandr Azatov ◽

Miguel Vanvlasselaer ◽

Wen Yin

Keyword(s):

Phase Transition ◽

Dark Matter ◽

Electroweak Phase Transition ◽

First Order ◽

Matter Production ◽

First Order Phase Transition ◽

Relic Abundance ◽

Higgs Portal ◽

First Order Phase ◽

Gravitational Background

Abstract In this paper we present a novel mechanism for producing the observed Dark Matter (DM) relic abundance during the First Order Phase Transition (FOPT) in the early universe. We show that the bubble expansion with ultra-relativistic velocities can lead to the abundance of DM particles with masses much larger than the scale of the transition. We study this non-thermal production mechanism in the context of a generic phase transition and the electroweak phase transition. The application of the mechanism to the Higgs portal DM as well as the signal in the Stochastic Gravitational Background are discussed.

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