Негейзенберговский ферримагентик с одноионной анизотропией

We have investigated the effect of single-ion anisotropy of the "easy plane" type on the phase states of a ferrimagnet with S = 1 and σ=1/2 sublattices and non-Heisenberg (bilinear and biquadratic in spins) exchange interaction for the sublattice with S = 1. It is shown that taking into account both the non-Heisenberg exchange interaction and the single-ion anisotropy of the sublattice with S = 1 leads to the realization of a phase with vector order parameters (ferrimagnetic phase) and a phase characterized by both vector and tensor order parameters (quadrupole-ferrimagnetic). It is shown that taking into account single-ion anisotropy changes the type of phase transition in comparison with an isotropic non-Heisenberg ferrimagnet. A phase diagram is constructed, and the condition for the compensation of the sublattice spins is determined.

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New phase transition induced by Ising-type impurity in easy-plane-type antiferromagnet with quantum fluctuation: NMR study of CsCu1−xCoxCl3

Physica B Condensed Matter ◽

10.1016/s0921-4526(99)02732-5 ◽

2000 ◽

Vol 284-288 ◽

pp. 1531-1532

Author(s):

Junichirou Hirano ◽

Shizumasa Ueda ◽

Meiro Chiba ◽

Toshio Ono ◽

Hidekazu Tanaka ◽

...

Keyword(s):

Phase Transition ◽

Quantum Fluctuation ◽

Easy Plane ◽

Plane Type ◽

Nmr Study ◽

New Phase

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Ferrimagnetic phase transition in the system Li0.5Fe2.52−x GaxO4 in the vicinity of the multicritical point of the x-T phase diagram

Journal of Experimental and Theoretical Physics ◽

10.1134/1.558603 ◽

1998 ◽

Vol 87 (6) ◽

pp. 1122-1128 ◽

Cited By ~ 2

Author(s):

N. N. Efimova ◽

M. B. Ustimenkova

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Multicritical Point ◽

Ferrimagnetic Phase ◽

T Phase

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Electric properties of olive oil under pressure

European Food Research and Technology ◽

10.1007/s00217-021-03761-7 ◽

2021 ◽

Author(s):

L. T. Pawlicki ◽

R. M. Siegoczyński ◽

S. Ptasznik ◽

K. Marszałek

Keyword(s):

Molecular Structure ◽

Phase Transition ◽

Phase Diagram ◽

Phase Transitions ◽

Olive Oil ◽

Material Parameters ◽

First Order ◽

Long Time ◽

Capacitive Reactance ◽

First Order Phase

AbstractThe main purpose of the experiment was a thermodynamic research with use of the electric methods chosen. The substance examined was olive oil. The paper presents the resistance, capacitive reactance, relative permittivity and resistivity of olive. Compression was applied with two mean velocities up to 450 MPa. The results were shown as functions of pressure and time and depicted on the impedance phase diagram. The three first order phase transitions have been detected. All the changes in material parameters were observed during phase transitions. The material parameters measured turned out to be the much more sensitive long-time phase transition factors than temperature. The values of material parameters and their dependence on pressure and time were compared with the molecular structure, arrangement of molecules and interactions between them. Knowledge about olive oil parameters change with pressure and its phase transitions is very important for olive oil production and conservation.

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Critical point of a para–ferrimagnetic phase transition of the ANNNI model in a field

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/24/43/436006 ◽

2012 ◽

Vol 24 (43) ◽

pp. 436006 ◽

Cited By ~ 2

Author(s):

J Sznajd

Keyword(s):

Phase Transition ◽

Critical Point ◽

Annni Model ◽

Ferrimagnetic Phase

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Rem and Rheed Studies of Pb Adsorption on Si(111)

MRS Proceedings ◽

10.1557/proc-280-109 ◽

1992 ◽

Vol 280 ◽

Cited By ~ 1

Author(s):

Yasumasa Tanishiro ◽

Masahiko Fukuyamaand ◽

Katsumichi Yagi

Keyword(s):

Phase Transition ◽

Heat Treatment ◽

Phase Diagram ◽

Surface Structures ◽

Structure Changes ◽

Incommensurate Structures

ABSTRACTStructure changes of Si(111)-Pb surfaces due to deposition and heat treatment are studied by REM-RHEED. Surface structures observed are summarized as a phase diagram. Formation of an incommensurate layer(α) and a phase transition between incommensurate structures of α and α' is described.

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SUPERCONDUCTING PHASE TRANSITION IN THE NAMBU–JONA-LASINIO MODEL

Modern Physics Letters A ◽

10.1142/s0217732301004339 ◽

2001 ◽

Vol 16 (17) ◽

pp. 1129-1138 ◽

Cited By ~ 13

Author(s):

M. SADZIKOWSKI

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Phase Transitions ◽

Superconducting Phase ◽

Coupling Constants ◽

Coupling Constant ◽

Rich Phase ◽

Quark Interaction ◽

Quark Coupling ◽

Superconducting Phase Transition

The Nambu–Bogoliubov–de Gennes method is applied to the problem of superconducting QCD. The effective quark–quark interaction is described within the framework of the Nambu–Jona-Lasinio model. The details of the phase diagram are given as a function of the strength of the quark–quark coupling constant G′. It is found that there is no superconducting phase transition when one uses the relation between the coupling constants G′ and G of the Nambu–Jona-Lasinio model which follows from the Fierz transformation. However, for other values of G′ one can find a rich phase structure containing both the chiral and the superconducting phase transitions.

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On SU(3) Effective Models and Chiral Phase Transition

Advances in High Energy Physics ◽

10.1155/2015/563428 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Abdel Nasser Tawfik ◽

Niseem Magdy

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Lattice Qcd ◽

High Energy ◽

Particle Model ◽

Chiral Phase ◽

Chiral Phase Transition ◽

Thermal Models ◽

Qcd Phase Diagram ◽

Freeze Out

Sensitivity of Polyakov Nambu-Jona-Lasinio (PNJL) model and Polyakov linear sigma-model (PLSM) has been utilized in studying QCD phase-diagram. From quasi-particle model (QPM) a gluonic sector is integrated into LSM. The hadron resonance gas (HRG) model is used in calculating the thermal and dense dependence of quark-antiquark condensate. We review these four models with respect to their descriptions for the chiral phase transition. We analyze the chiral order parameter, normalized net-strange condensate, and chiral phase-diagram and compare the results with recent lattice calculations. We find that PLSM chiral boundary is located in upper band of the lattice QCD calculations and agree well with the freeze-out results deduced from various high-energy experiments and thermal models. Also, we find that the chiral temperature calculated from HRG is larger than that from PLSM. This is also larger than the freeze-out temperatures calculated in lattice QCD and deduced from experiments and thermal models. The corresponding temperature and chemical potential are very similar to that of PLSM. Although the results from PNJL and QLSM keep the same behavior, their chiral temperature is higher than that of PLSM and HRG. This might be interpreted due the very heavy quark masses implemented in both models.

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The Microscopic Theory of Superfluidity and Superconductivity Driven by Single Particle and Pair Condensation of Attracting Bosons

International Journal of Modern Physics B ◽

10.1142/s0217979298001289 ◽

1998 ◽

Vol 12 (21) ◽

pp. 2151-2224 ◽

Cited By ~ 14

Author(s):

S. Dzhumanov

Keyword(s):

Phase Transition ◽

Order Phase Transition ◽

Single Particle ◽

Microscopic Theory ◽

Order Parameters ◽

Coupling Constants ◽

Bose Liquid ◽

Composite Bosons ◽

Superfluidity And Superconductivity ◽

Pair Condensation

A original microscopic theory of superfluidity and superconductivity driven by the single particle (SPC) and pair condensation (PC) of attracting bosons both in Fermi and in Bose systems is developed. This theory (as distinct from the existing theories) for Fermi systems contains two order parameters Δ F and Δ B characterizing the attracting fermion pairs and boson pairs, respectively. In such systems superconducting (SC) phase transition is accompanied, as a rule, by the formation of k-space composite bosons (e.g. Cooper pairs and bipolarons) with their subsequent transition to the superfluid (SF) state by attractive SPC and PC. A novel Fermi-liquid and SF Bose-liquid theories are elaborated for description this two-stage Fermi–Bose-liquid (FBL) scenario of SC (or SF) transition. The crossover from k- to real (r)-space pairing regime for BCS-like coupling constants γ F ≃ 0.7-0.9 and the irrelevance of r-space pairs to the superconductivity are shown. The developed SF Bose-liquid theory predicts the first-order phase transition SPC ↔ PC of attracting 3d-bosons with the kink-like behaviors of all SC (SF) parameters near [Formula: see text] in accordance with the observations in 4 He , 3 He and superconductors. It is argued that the coexistence of the order parameters Δ F and Δ B leads to the superconductivity by two FBL scenarios. One of these scenarios is realized in the so-called fermion (type I, II and III) superconductors (FSC) (where formation of k-space composite bosons and their condensation occur at the same temperature) and the other in the boson (type II and III) superconductors (BSC) (where BCS-like pairing take place in the normal state with manifesting of the second-order phase transition and opening of the pseudogap at T=T F > T c ). There the gapless superfluidity (superconductivity) is caused by the gapless excitation spectrum of bosons at [Formula: see text] and not by the presence of point or line nodes of the BCS-like gap Δ F assumed in some s-, p- and d-pairing models. The 3D- and 2D-insulator–metal–superconductor phase diagrams are presented. The necessary and sufficient microscopic criterions for superfluidity is formulated. The theory proposed are in close agreement with the observations in 4 He , 3 He , superconductors, nuclear and neutron star matter, cosmology, etc.

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