Finite-Temperature Bose-Einstein Condensation in Interacting Boson System

Thermodynamical properties of an interacting boson system at finite temperatures and zero chemical potential are studied within the framework of the Skyrme-like mean-field toy model. It is assumed that the mean field contains both attractive and repulsive terms. Self-consistency relations between the mean field and thermodynamic functions are derived. It is shown that, for sufficiently strong attractive interactions, this system develops a first-order phase transition via the formation of a Bose condensate. An interesting prediction of the model is that the condensed phase is characterized by a constant total density of particles. It is shown that the energy density exhibits a jump at the critical temperature.

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Phase diagram of the selfinteracting particle-antiparticle boson system

Journal of Physics and Electronics ◽

10.15421/332101 ◽

2021 ◽

Vol 29 (1) ◽

pp. 5-14

Author(s):

D. Anchishkin ◽

V. Gnatovskyy ◽

D. Zhuravel ◽

V. Karpenko

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Phase Diagrams ◽

Canonical Ensemble ◽

Bose Condensate ◽

Mean Field ◽

Thermodynamic Quantities ◽

Boson System ◽

The Mean

A system of interacting relativistic bosons at finite temperatures and isospin densities is studied within the framework of the Skyrmelike meanfield model. The mean field contains both attractive and repulsive terms. The consideration is taken within the framework of the Canonical Ensemble and the isospindensity dependencies of thermodynamic quantities is obtained, in particular as the phase diagrams. It is shown that in such a system, in addition to the formation of a BoseEinstein condensate, a liquidgas phase transition is possible. We prove that the multiboson system develops the Bose condensate for particles of highdensity component only.

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A FIRST ORDER PHASE TRANSITION IN ISING FERRIMAGNETS

Modern Physics Letters B ◽

10.1142/s0217984995001339 ◽

1995 ◽

Vol 09 (21) ◽

pp. 1347-1351 ◽

Cited By ~ 1

Author(s):

HASAN M. AL MUKADAM ◽

DIMO I. UZUNOV

Keyword(s):

Phase Transition ◽

Order Parameter ◽

Mean Field Theory ◽

Mean Field ◽

First Order ◽

First Order Phase Transition ◽

Exchange Constants ◽

The Mean ◽

First Order Phase ◽

Ising Spins

The mean field theory is used for the analysis of a two-sublattice system of Ising spins, which describes ferro-, antiferro-, and ferrimagnetic orderings. It is proven that the phase transition in these systems is of a first order when the exchange constants of the sublattices are different. The free energy, the order parameter profiles and the latent heat of the phase transition are calculated for almost equivalent sublattices.

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Notizen: Monte-Carlo Simulation of a Two-dimensional Dipolar Lattice

Zeitschrift für Naturforschung A ◽

10.1515/zna-1977-1119 ◽

1977 ◽

Vol 32 (11) ◽

pp. 1320-1322 ◽

Cited By ~ 1

Author(s):

S. Romano

Keyword(s):

Monte Carlo ◽

Mean Field Theory ◽

Mean Field ◽

Square Lattice ◽

Electrostatic Energy ◽

Two Dimensional ◽

First Order ◽

First Order Phase Transition ◽

The Mean ◽

First Order Phase

Abstract Monte-Carlo calculations were carried out on a system consisting of 256 point-dipoles, whose centres are fixed in a two-dimensional square lattice with the usual boundary condition; the Epstein-Ewald-Kornfeld algorithm was used in evaluating the electrostatic energy. No evidence of a first-order phase transition was found, and the results suggest there might be a second-order one. Additional calculations were carrierd out using the mean-field theory, which was found to overestimate the transition temperature by about a factor two.

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QCD susceptibilities in the presence of the chiral chemical potential

Modern Physics Letters A ◽

10.1142/s0217732320501370 ◽

2020 ◽

Vol 35 (16) ◽

pp. 2050137

Author(s):

Run-Lin Liu ◽

Hong-Shi Zong

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Chemical Potential ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Chiral Phase ◽

First Order Phase Transition ◽

Phase Transition Region ◽

First Order Phase

In this paper, chiral chemical potential [Formula: see text] is introduced to investigate the QCD susceptibilities and chiral phase transition within the Polyakov-loop-extended Nambu–Jona-Lasinio models in the mean-field approximation. We concentrate on the effect of chiral chemical potential on the phase diagram and the QCD susceptibilities. Moreover, it is worth noting that chiral chemical potential has more and more prominent impact on the susceptibilities and the phase diagram with the decrease of temperature based on our results, which coincides with the prediction that the chiral symmetry is dynamically broken in the first-order phase transition region and gets partly restored in the crossover region.

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Phase Transitions and Bose–Einstein Condensation in Alpha-Nucleon Matter

Ukrainian Journal of Physics ◽

10.15407/ujpe64.8.745 ◽

2019 ◽

Vol 64 (8) ◽

pp. 745

Author(s):

L. M. Satarov ◽

I. N. Mishustin ◽

A. Motornenko ◽

V. Vovchenko ◽

M. I. Gorenstein ◽

...

Keyword(s):

Phase Diagram ◽

Phase Transitions ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Einstein Condensation ◽

Bose Einstein Condensation ◽

Nucleon Matter ◽

Bose Einstein ◽

First Order Phase

The equation of state and the phase diagram of an isospin-symmetric chemically equilibrated mixture of a particles and nucleons (N) are studied in the mean-field approximation. We use a Skyrme-like parametrization of mean-field potentials as functions of the partial densities of particles. The parameters of these potentials are chosen by fitting the known properties of pure N- and pure a-matters at zero temperature. The sensitivity of results to the choice of the aN attraction strength is investigated. The phase diagram of the a − N mixture is studied with a special attention paid to the liquid-gas phase transitions and the Bose–Einstein condensation of a particles. We have found two first-order phase transitions, stable and metastable, which differ significantly by the fractions of a’s. It is shown that the states with a condensate are metastable.

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Low-temperature dielectric anomaly arising from electronic phase separation at the Mott insulator-metal transition

npj Quantum Materials ◽

10.1038/s41535-020-00307-0 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

A. Pustogow ◽

R. Rösslhuber ◽

Y. Tan ◽

E. Uykur ◽

A. Böhme ◽

...

Keyword(s):

Phase Separation ◽

Mean Field Theory ◽

Mean Field ◽

Coulomb Repulsion ◽

Mott Insulator ◽

Electronic Phase Separation ◽

First Order Phase Transition ◽

Electronic Phase ◽

Insulator Metal Transition ◽

First Order Phase

AbstractCoulomb repulsion among conduction electrons in solids hinders their motion and leads to a rise in resistivity. A regime of electronic phase separation is expected at the first-order phase transition between a correlated metal and a paramagnetic Mott insulator, but remains unexplored experimentally as well as theoretically nearby T = 0. We approach this issue by assessing the complex permittivity via dielectric spectroscopy, which provides vivid mapping of the Mott transition and deep insight into its microscopic nature. Our experiments utilizing both physical pressure and chemical substitution consistently reveal a strong enhancement of the quasi-static dielectric constant ε1 when correlations are tuned through the critical value. All experimental trends are captured by dynamical mean-field theory of the single-band Hubbard model supplemented by percolation theory. Our findings suggest a similar ’dielectric catastrophe’ in many other correlated materials and explain previous observations that were assigned to multiferroicity or ferroelectricity.

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Modification of charge density wave fluctuations by charge perturbations

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20020359 ◽

2002 ◽

Vol 12 (9) ◽

pp. 77-78

Author(s):

S. N. Artemenko

Keyword(s):

Electric Field ◽

Linear Response ◽

Chemical Potential ◽

Density Wave ◽

Mean Field ◽

Phase Fluctuations ◽

Fluctuation Dissipation ◽

Fluctuation Dissipation Theorem ◽

The Mean ◽

Field Transition

Spectral density of fluctuations of the CDW phase are calculated taking into account electric field induced by phase fluctuations. The approach based upon the fluctuation-dissipation theorem (FDT) combined with equations of linear response of the CDW conductor is used. Fluctuating electric field is found to suppress fluctuations of the phase, while fluctuations of the electric potential are sizeable. This suggests that transition from the CDW to the normal state (which is usually observed well below the mean-field transition temperature) may he provoked by fluctuations of the chemical potential, rather than by destruction of the CDW coherence between conducting chains due to phase fluctuations.

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Locating the critical end point using the linear sigma model coupled to quarks.

EPJ Web of Conferences ◽

10.1051/epjconf/201817202003 ◽

2018 ◽

Vol 172 ◽

pp. 02003

Author(s):

Alejandro Ayala ◽

J. A. Flores ◽

L. A. Hernández ◽

S. Hernández-Ortiz

Keyword(s):

Sigma Model ◽

Chemical Potential ◽

Potential Temperature ◽

Mean Field ◽

Field Approximation ◽

Baryon Density ◽

Linear Sigma Model ◽

Mean Field Approximation ◽

End Point ◽

The Mean

We use the linear sigma model coupled to quarks to compute the effective potential beyond the mean field approximation, including the contribution of the ring diagrams at finite temperature and baryon density. We determine the model couplings and use them to study the phase diagram in the baryon chemical potential-temperature plane and to locate the Critical End Point.

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Evidence for spin current driven Bose-Einstein condensation of magnons

Nature Communications ◽

10.1038/s41467-021-26790-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

B. Divinskiy ◽

H. Merbouche ◽

V. E. Demidov ◽

K. O. Nikolaev ◽

L. Soumah ◽

...

Keyword(s):

Room Temperature ◽

Chemical Potential ◽

Spin Current ◽

Einstein Condensation ◽

Electronic Control ◽

Spintronic Devices ◽

Bose Einstein Condensation ◽

Magnetic Insulators ◽

Spatially Extended ◽

Bose Einstein

AbstractThe quanta of magnetic excitations – magnons – are known for their unique ability to undergo Bose-Einstein condensation at room temperature. This fascinating phenomenon reveals itself as a spontaneous formation of a coherent state under the influence of incoherent stimuli. Spin currents have been predicted to offer electronic control of Bose-Einstein condensates, but this phenomenon has not been experimentally evidenced up to now. Here we show that current-driven Bose-Einstein condensation can be achieved in nanometer-thick films of magnetic insulators with tailored nonlinearities and minimized magnon interactions. We demonstrate that, above a certain threshold, magnons injected by the spin current overpopulate the lowest-energy level forming a highly coherent spatially extended state. We quantify the chemical potential of the driven magnon gas and show that, at the critical current, it reaches the energy of the lowest magnon level. Our results pave the way for implementation of integrated microscopic quantum magnonic and spintronic devices.

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