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Related papers: An Estimation of Phase Transition

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We have studied the Ce valence as a function of pressure in CeRhIn5 at 300 K and at 22 K using x-ray absorption spectroscopy in partial fluorescent yield mode. At room temperature, we found no detectable change in Ce valence greater than…

Two-scalar theories at high temperature exhibit a rich spectrum of possible critical behaviour, with a second or first order phase transition. In the vicinity of the critical temperature one can observe critical exponents, tricritical…

High Energy Physics - Phenomenology · Physics 2010-11-01 S. Bornholdt , N. Tetradis , C. Wetterich

We calculate analytically the phase boundary for a nonequilibrium phase transition in a one-dimensional array of coupled, overdamped parametric harmonic oscillators in the limit of strong and weak spatial coupling. Our results show that the…

Statistical Mechanics · Physics 2009-11-07 J. Farago , C. Van den Broeck

Synchrotron x-ray diffraction experiments have been carried out on Eu metal at ambient temperature to pressures as high as 92 GPa (0.92 Mbar). Following the well-known bcc-to-hcp transition at 12 GPa, a mixed phase region is observed from…

Materials Science · Physics 2015-05-20 W. Bi , Y. Meng , R. S. Kumar , A. L. Cornelius , W. W. Tipton , R. G. Hennig , Y. Zhang , C. Chen , J. S. Schilling

Phase transitions of reaction-diffusion systems with site occupation restriction and with particle creation that requires n=3,4 parents, whereas explicit diffusion of single particles (A) is present are investigated in low dimensions by…

Statistical Mechanics · Physics 2009-11-07 Geza Odor

We show, that the standard model of phase transition can be unified with the gradient model of phase transitions using the description in terms of the gradient of order parameter. The generalization of the gradient theory of phase…

Statistical Mechanics · Physics 2012-06-21 B. I. Lev , A. G. Zagorodny

We discuss a numerical analysis employing the density of partition function zeroes which permits effective distinction between phase transitions of first and second order, elucidates crossover between such phase transitions and gives a new…

Statistical Mechanics · Physics 2007-05-23 Wolfhard Janke , Ralph Kenna

The following is a thermodynamic analysis of a III order (and some aspects of a IV order) phase transition. Such a transition can occur in a superconductor if the normal state is a diamagnet. The equation for a phase boundary in an H-T (H…

Superconductivity · Physics 2016-08-31 Pradeep Kumar

Einstein-dilaton-$U(2)$ gauge field theory is considered in a spacetime characterised by $\alpha$ and $z$, which are the hyperscaling violation factor and the dynamical critical exponent respectively. We obtain the critical values of…

High Energy Physics - Theory · Physics 2016-09-28 Miok Park , Jiwon Park , Jae-Hyuk Oh

The existence of second-order structural phase transition in the SnS at a pressure of 16 GPa has been proved theoretically. The calculation is performed using the plane-wave pseudopotential approach to density-functional theory within the…

Materials Science · Physics 2015-06-19 F. M. Hashimzade , D. A. Huseinova , Z. A. Jahangirli , B. H. Mehdiyev

We investigate the high-pressure phase transitions in BiFeO3 by single crystal and powder x-ray diffraction, as well as single crystal Raman spectroscopy. Six phase transitions are reported in the 0-60 GPa range. At low pressures, up to 15…

Equilibrium phase transitions may be defined as nonanalytic points of thermodynamic functions, e.g., of the canonical free energy. Given a certain physical system, it is of interest to understand which properties of the system account for…

Statistical Mechanics · Physics 2008-01-08 Michael Kastner

Based on a previously proposed thermodynamic analysis, we study the relative stabilities of five Si phases under uniaxial compression using ab initio methods. The five phases are diamond, beta-tin, sh, sc, and hcp structures. The possible…

Materials Science · Physics 2009-11-07 C. Cheng

The recent paper nucl-th/0208024 by Moretto et al. is commented: Their picture of nuclear phase transition in terms of macroscopic control parameters, temperature and pressure, is irrelevant. Their criticism of order-disorder…

Nuclear Theory · Physics 2007-05-23 D. H. E. Gross

We prove that under certain conditions, phase separation is enough to sustain a regime in which current flows along the concentration gradient, a phenomenon which is known in the literature as \textit{uphill diffusion}. The model we…

Mathematical Physics · Physics 2019-05-22 Roberto Boccagna

Ji et al. report performing X-ray diffraction on hydrogen compressed to over 250 GPa (https://doi.org/10.1038/s41586-019-1565-9). It is a remarkable technical achievement. However, the experimental data presented and discussed in the paper…

Materials Science · Physics 2019-10-25 L. Dubrovinsky , N. Dubrovinskaia , M. I. Katsnelson

In this article we study the phase transition phenomenon for the Ising model under the action of a non-uniform external magnetic field. We show that the Ising model on the hypercubic lattice with a summable magnetic field has a first-order…

Mathematical Physics · Physics 2017-08-01 Rodrigo Bissacot , Leandro Cioletti

In a field-theoretical context, we consider the Euclidean $(\phi^4+\phi^6)_D$ model compactified in one of the spatial dimensions. We are able to determine the dependence of the transition temperature ($T_{c}$)for a system described by this…

High Energy Physics - Theory · Physics 2007-05-23 C. A. Linhares , A. P. C. Malbouisson , I. Roditi

In the canonical formalism of statistical physics, a signature of a first order phase transition for finite systems is the bimodal distribution of an order parameter. Previous thermodynamical studies of nuclear sources produced in heavy-ion…

Transport and magnetic studies of PbTaSe$_2$ under pressure suggest existence of two superconducting phases with the low temperature phase boundary at $\sim 0.25$ GPa that is defined by a very sharp, first order, phase transition. The first…