Lattice cluster theory of associating telechelic polymers. III. Order parameter and average degree of self-assembly, transition temperature, and specific heat

2012 ◽  
Vol 136 (19) ◽  
pp. 194902 ◽  
Author(s):  
Jacek Dudowicz ◽  
Karl F. Freed ◽  
Jack F. Douglas
Keyword(s):  
Transition Temperature ◽  
Specific Heat ◽  
Self Assembly ◽  
Order Parameter ◽  
Average Degree ◽  
Telechelic Polymers ◽  
Cluster Theory

OFF-AXIAL DYNAMIC SYMMETRY BREAKING IN UNIAXIALLY ANISOTROPIC HEISENBERG FERROMAGNET

2001 ◽  
Vol 12 (05) ◽  
pp. 709-716 ◽  
Author(s):  
MUKTISH ACHARYYA
Keyword(s):  
Magnetic Field ◽  
Monte Carlo ◽  
Transition Temperature ◽  
Monte Carlo Method ◽  
Symmetry Breaking ◽  
Specific Heat ◽  
Order Parameter ◽  
Three Dimensions ◽  
Heisenberg Ferromagnet ◽  
Dynamic Symmetry

The dynamics of uniaxially (along the z direction) anisotropic Heisenberg ferromagnets (in three dimensions) in the presence of a magnetic field varying sinusoidally in time (along the x-direction only) is studied by Monte Carlo method using Metropolis rate. The time averaged (over a complete cycle of the oscillating field) value of z component of the magnetization continuously vanishes at a particular transition temperature associated with a dynamic symmetry breaking of mz-hx loop. The temperature variation of dynamic order parameter and the dynamic specific heat for different values of the anisotropy show that the transition temperature increases as the strength of anisotropy increases.

scholarly journals The Intramolecular Pressure and the Extension of the Critical Point’s Influence Zone on the Order Parameter

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jose Luis Rivera ◽  
Homero Nicanor-Guzman ◽  
Roberto Guerra-Gonzalez
Keyword(s):  
Transition Temperature ◽  
Critical Temperature ◽  
Liquid Phase ◽  
Order Parameter ◽  
Bulk Liquid ◽  
Influence Zone ◽  
Molecular Potential ◽  
Liquid Phases ◽  
Dynamics Simulations ◽  
Wide Zone

The critical point affects the coexistence behavior of the vapor-liquid equilibrium densities. The length of the critical influence zone is under debate because for some properties, like shear viscosity, the extension is only a few degrees, while for others, such as the density order parameter, the critical influence zone covers up to hundreds of degrees below the critical temperature. Here we show that, for ethane, the experimental critical influence zone covers a wide zone of tens of degrees (below the critical temperature) down to a transition temperature, at which the apparent critical influence zone vanishes, and the transition temperature can be predicted through a pressure analysis of the coexisting bulk liquid phase, using a simple molecular potential. The liquid phases within the apparent critical influence zone show low densities, making them behave internally like their corresponding vapor phases. Therefore, Molecular Dynamics simulations reveal that the experimentally observed wide extension of the critical influence zone is the result of a vapor-like effect due to low bulk liquid phase densities.

scholarly journals Perylene-like Dyes in Liquid Crystalline Media

1996 ◽  
Vol 51 (7) ◽  
pp. 843-850 ◽  
Author(s):  
Ewa Mykowska ◽  
Danuta Bauman
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Order Parameter ◽  
Liquid Crystalline ◽  
Fluorescent Dyes ◽  
Liquid Crystal Display ◽  
Isotropic Phase ◽  
Display Devices ◽  
Electrooptical Properties ◽  
Derivatives Of

Abstract The spectral and electrooptical properties of some dichroic fluorescent dyes (derivatives of 3.4,9,10-perylenetetracorboxylic acid and of 3,4,9-perylenetricarboxylic acid) in isotropic solvents and nematic liquid crystals have been studied. The order parameter of the dyes in the anisotropic matrices has been determined by means of optical spectroscopy methods. Moreover, the influence of the dye addition on the nematic-isotropic phase transition temperature of the pure host has been investigated. It was found that some of the dyes studied can be utilized in guest-host liquid crystal display devices.

Programming Self-Assembly and Stimuli-Triggered Response of Hydrophilic Telechelic Polymers with Sequence-Encoded Hydrophobic Initiators

2020 ◽  
Vol 53 (17) ◽  
pp. 7285-7297 ◽  
Author(s):  
Adrian Moreno ◽  
Juan C. Ronda ◽  
Virginia Cádiz ◽  
Marina Galià ◽  
Virgil Percec ◽  
...  
Keyword(s):  
Self Assembly ◽  
Telechelic Polymers

EFFECT OF COOLING RATE ON THE TRANSITION TEMPERATURE IN Bi–Pb–Sr–Ca–Cu–O SYSTEM

1990 ◽  
Vol 04 (04) ◽  
pp. 293-299
Author(s):  
YUGUI WANG ◽  
JINSONG WANG ◽  
NANLIN WANG ◽  
XINPING JIAO ◽  
GUCHANG HAN ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Specific Heat ◽  
Cooling Rate ◽  
Volume Fraction ◽  
Oxygen Deficiency ◽  
Ac Susceptibility ◽  
Rapid Quenching ◽  
Nominal Composition ◽  
Unit Cell Size ◽  
Superconducting Volume Fraction

The resistance and ac susceptibility measurements show that cooling rate of the cast-annealing samples in heat treatment process has some effect on the 110 K superconducting phase in Bi–Pb–Sr–Ca–Cu–O system. Rapid quenching of the sample in air from 845°C causes oxygen deficiency in lattice and brings about a trifling change of unit cell size along c-axis direction. The dc magnetization and specific heat anomaly ∆c measurements demonstrate that fast cooling rate can reduce the transition temperature of high T c phase and the lower critical field, and weaken the pinning forces for vertex lines. The peak value of specific heat anomaly of the sample with nominal composition of Bi 1.7 Pb 0.3 Sr 2 Ca 2 Cu 4.5 O y is still small in comparison with YBa 2 Cu 3 O 7. From the magnetization curve we can estimate that the superconducting volume fraction is about 20%.

scholarly journals Vibronic Mechanism of High Tc Superconductivity

2003 ◽  
Vol 17 (18n20) ◽  
pp. 3266-3270 ◽  
Author(s):  
M. Tachiki ◽  
T. Egami ◽  
M. Machida
Keyword(s):  
Transition Temperature ◽  
Order Parameter ◽  
Cuprate Superconductors ◽  
High Temperature Superconductivity ◽  
Attractive Interaction ◽  
Low Frequencies ◽  
High Tc ◽  
Eliashberg Theory ◽  
Bond Stretching ◽  
Vibronic Effect

When phonons strongly mix with electron charge fluctuations with low frequencies, the phonon mediated attractive interaction between electrons is strongly enhanced. The occurrence of the mixing has been indicated by the neutron scattering experimental results that the dispersion of the in-plane Cu–O bond-stretching mode in the high Tc cuprate superconductors is strongly softened near the zone boundary. We propose that the phonon mediated attractive interaction strongly enhanced by the vibronic effect can form a basis for the phonon mechanism of high temperature superconductivity. With the Eliashberg theory and with the electronic structure determined by ARPES and the electronic dielectric function obtained by the softened dispersion of the in-pane Cu–O stretching mode, we calculated the transition temperature and the order parameter at the transition temperature. The order parameter is of the d(x2-y2) symmetry and the transition temperature is well in excess of 100 K.

DENSITY OF STATES AND ORDER PARAMETER IN DIRTY SUPERCONDUCTORS WITH A WEAKLY BROKEN d-WAVE SYMMETRY

1996 ◽  
Vol 10 (12) ◽  
pp. 537-544 ◽  
Author(s):  
SERGEI V. POKROVSKY
Keyword(s):  
Phase Transition ◽  
Transition Temperature ◽  
Density Of States ◽  
Order Parameter ◽  
Zero Temperature ◽  
Scattering Rate ◽  
Wave Symmetry ◽  
Direct Calculations ◽  
D Wave ◽  
Gapless Superconductivity

It is shown by direct calculations that in a superconductor with a slightly violated d-wave symmetry of the order parameter (OP) the impurity driven phase transition from the gapless superconductivity to a state with a finite gap takes place at zero temperature. The corresponding scattering rate is close to the value at which the superconductivity vanishes in the d-superconductor. The behavior of the transition temperature, the OP and the density of states (DOS) is analyzed. The model is plausibly relevant to the BSCCO 2:2:1:2.

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