Exact Order-Parameter Distribution for Critical Mean-Field Percolation and Critical Aggregation

Of late, the study of BCS-BEC crossover in the presence of weak random impurity is an interesting issue. In this proceedings we study the effect of this disorder which is included through the Nozières and Smith-Rink theory of superconducting fluctuations. In the weak regime, the random potential leaves an effect on the superconducting order parameter but it spares the chemical potential. Here we present the exact behavior of the mean field quantities as a function of the disorder by self-consistently solving the coupled equations.

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CRITICAL DIMENSIONS OF SYSTEMS WITH JOINT MULTICRITICAL AND LIFSHITZ-POINT-LIKE BEHAVIOR

Modern Physics Letters B ◽

10.1142/s021798491102708x ◽

2011 ◽

Vol 25 (22) ◽

pp. 1839-1845 ◽

Cited By ~ 2

Author(s):

ARTEM V. BABICH ◽

LESYA N. KITCENKO ◽

VYACHESLAV F. KLEPIKOV

Keyword(s):

Field Theory ◽

Critical Phenomena ◽

Critical Points ◽

Order Parameter ◽

Mean Field Theory ◽

Mean Field ◽

Critical Dimensions ◽

Lifshitz Point ◽

The Mean ◽

Derivatives Of

In this article, we consider a model that allows one to describe critical phenomena in systems with higher powers and derivatives of order parameter. The systems considered have critical points with joint multicritical and Lifshitz-point-like properties. We assess the lower and upper critical dimensions of these systems. These calculation enable us to find the fluctuation region where the mean field theory description does not work.

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Universal scaling of the order-parameter distribution in strongly disordered superconductors

Physical Review B ◽

10.1103/physrevb.87.184509 ◽

2013 ◽

Vol 87 (18) ◽

Cited By ~ 40

Author(s):

G. Lemarié ◽

A. Kamlapure ◽

D. Bucheli ◽

L. Benfatto ◽

J. Lorenzana ◽

...

Keyword(s):

Order Parameter ◽

Parameter Distribution ◽

Universal Scaling ◽

Disordered Superconductors

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Phase transitions in perovskites near the tricritical point: an experimental study of KMn1–xCaxF3 and SrTiO3

Mineralogical Magazine ◽

10.1180/002646100549878 ◽

2000 ◽

Vol 64 (6) ◽

pp. 971-982 ◽

Cited By ~ 14

Author(s):

M. C. Gallardo ◽

F. J. Romero ◽

S. A. Hayward ◽

E. K. H. Salje ◽

J. del Cerro

Keyword(s):

Experimental Data ◽

Experimental Study ◽

Phase Transitions ◽

Order Parameter ◽

Tricritical Point ◽

Mean Field ◽

Calorimetric Data ◽

X Ray ◽

First Order ◽

Field Behaviour

AbstractWe present experimental data for the Pm3m-I4/mcm phase transitions in the perovskite crystals KMn1-xCaxF3 and SrTiO3. Comparison of calorimetric data (latent heat and specific heat) with order parameter data (measured with X-ray rocking methods) indicates that these transitions follow mean-field behaviour, and may be described using Landau potentials where the free energy expansion includes terms up to Q6. This potential is characteristic of transitions close to the tricritical point. Comparison of the behaviour of SrTiO3 and KMnF3 indicates that KMnF3 is closer to the tricritical point; a small amount of substitution of Ca for Mn causes the transition to cross the tricritical point from first order to second order behaviour.

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Order Parameter, Mean-Field Theory, and the Ideal Bose Gas

Physical Review ◽

10.1103/physrev.188.522 ◽

1969 ◽

Vol 188 (1) ◽

pp. 522-525 ◽

Cited By ~ 3

Author(s):

M. Schick ◽

P. R. Zilsel

Keyword(s):

Field Theory ◽

Order Parameter ◽

Mean Field Theory ◽

Mean Field ◽

Bose Gas ◽

Ideal Bose Gas ◽

The Ideal

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A MEAN FIELD STUDY OF THE PHASE TRANSITIONS IN A CLASS OF SYSTEMS WITH COMPLEX ORDER PARAMETERS

International Journal of Modern Physics B ◽

10.1142/s0217979294001688 ◽

1994 ◽

Vol 08 (28) ◽

pp. 3963-3986

Author(s):

EVGENIA J. BLAGOEVA

Keyword(s):

Phase Diagram ◽

Phase Transitions ◽

Order Parameter ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Unconventional Superconductors ◽

Complex Order ◽

The Mean ◽

Expansion Coefficients

A generalized Landau free energy for a complex order parameter expanded up to sixth-order is investigated using group theoretical arguments and the mean-field approximation. Results for the phase transitions that occur are presented. The phase diagram for all allowed values of the expansion coefficients is constructed with an emphasis placed on the influence of the anisotropy in the order parameter space. The results can be used in discussions of unconventional superconductors and modulated structural and magnetic orderings.

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