Electric Quadrupole Orders in f-Electron Systems on the fcc Lattice

2021 ◽  
Vol 1 ◽  
Keyword(s):  
Phase Diagram ◽  
Heavy Fermion ◽  
Electric Quadrupole ◽  
Electron Systems ◽  
Rich Phase ◽  
Partially Ordered ◽  
Fcc Lattice ◽  
Ordered Phases ◽  
Heavy Fermion Materials

We theoretically showed that electric quadrupoles in some heavy fermion materials exhibit a very rich phase diagram including unique partially-ordered phases stabilized by an interaction specific to these systems.

scholarly journals Experimental evidence for the existence of a second partially-ordered phase of ice VI

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ryo Yamane ◽  
Kazuki Komatsu ◽  
Jun Gouchi ◽  
Yoshiya Uwatoko ◽  
Shinichi Machida ◽  
...  
Keyword(s):  
Phase Diagram ◽  
High Pressure ◽  
Research Approach ◽  
Theoretical Studies ◽  
Partially Ordered ◽  
Structural Variety ◽  
Ordered Phases ◽  
New Form ◽  
Experimental And Theoretical Studies ◽  
Pressure Phase

AbstractIce exhibits extraordinary structural variety in its polymorphic structures. The existence of a new form of diversity in ice polymorphism has recently been debated in both experimental and theoretical studies, questioning whether hydrogen-disordered ice can transform into multiple hydrogen-ordered phases, contrary to the known one-to-one correspondence between disordered ice and its ordered phase. Here, we report a high-pressure phase, ice XIX, which is a second hydrogen-partially-ordered phase of ice VI. We demonstrate that disordered ice undergoes different manners of hydrogen ordering, which are thermodynamically controlled by pressure in the case of ice VI. Such multiplicity can appear in all disordered ice, and it widely provides a research approach to deepen our knowledge, for example of the crucial issues of ice: the centrosymmetry of hydrogen-ordered configurations and potentially induced (anti-)ferroelectricity. Ultimately, this research opens up the possibility of completing the phase diagram of ice.

scholarly journals Quasi-1D XY antiferromagnet Sr2Ni(SeO3)2Cl2 at Sakai-Takahashi phase diagram

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Kozlyakova ◽  
A. V. Moskin ◽  
P. S. Berdonosov ◽  
V. V. Gapontsev ◽  
S. V. Streltsov ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Long Range ◽  
Density Functional ◽  
Uniaxial Anisotropy ◽  
Exchange Interactions ◽  
Spin Liquid ◽  
Functional Theory ◽  
One Dimensional ◽  
Ordered Phases ◽  
Experimental Findings

AbstractUniform quasi-one-dimensional integer spin compounds are of interest as a potential realization of the Haldane conjecture of a gapped spin liquid. This phase, however, has to compete with magnetic anisotropy and long-range ordered phases, the implementation of which depends on the ratio of interchain J′ and intrachain J exchange interactions and both uniaxial D and rhombic E single-ion anisotropies. Strontium nickel selenite chloride, Sr2Ni(SeO3)2Cl2, is a spin-1 chain system which passes through a correlations regime at Tmax ~ 12 K to long-range order at TN = 6 K. Under external magnetic field it experiences the sequence of spin-flop at Bc1 = 9.0 T and spin-flip transitions Bc2 = 23.7 T prior to full saturation at Bsat = 31.0 T. Density functional theory provides values of the main exchange interactions and uniaxial anisotropy which corroborate the experimental findings. The values of J′/J = 0.083 and D/J = 0.357 place this compound into a hitherto unoccupied sector of the Sakai-Takahashi phase diagram.

TEM Characterization of Pseudotetragonal Mullite

2001 ◽  
Vol 7 (S2) ◽  
pp. 426-427
Author(s):  
Bradley R. Johnson ◽  
Waltraud M. Kriven
Keyword(s):  
Phase Diagram ◽  
Spatial Relationship ◽  
Equilibrium Structure ◽  
Lattice Parameters ◽  
Orthorhombic Structure ◽  
Containerless Processing ◽  
Rich Phase ◽  
Tem Characterization ◽  
Solution Field

Mullite (3Al2O3•2SiO2) exists in a solid solution field (∼57-63 mol% Al2O3) as the only stable compound in the Al2O3•SiO2 phase diagram at ambient pressures. Equilibrium 3:2 mullite has an orthorhombic structure with b>a (o-mullite). However, when initially crystallized from molecularly mixed, 3:2 precursors at temperatures < 1200°C, the first phase that forms has lattice parameters with a ≈b. This structure is often termed pseudotetragonal mullite (pt-mullite), since even when the ‘a’ and ‘b’ lattice parameters are identical, they are symmetrically independent. Pseudotetragonal mullite has been shown to contain approx. 70 mol% Al2O3. with increasing time and temperature, the structure gradually assimilates the residual SiO2, and the lattice parameters change, such that by 1400°C, the material has attained its equilibrium structure and composition.TEM was used to determine the spatial relationship between the crystalline phase and the residual, amorphous, SiO2-rich phase in pt-mullite. The starting materials were quenched, 3:2 mullite beads and fibers (made by containerless processing).

scholarly journals Hyperfine couplings as a probe of orbital anisotropy in heavy-fermion materials

2021 ◽  
Vol 104 (3) ◽  
Author(s):  
P. Menegasso ◽  
J. C. Souza ◽  
I. Vinograd ◽  
Z. Wang ◽  
S. P. Edwards ◽  
...  
Keyword(s):  
Heavy Fermion ◽  
Heavy Fermion Materials ◽  
Hyperfine Couplings

Phase diagram of ordered phases with L10 and L12 superlattices

1972 ◽  
Vol 15 (1) ◽  
pp. 138-140 ◽  
Author(s):  
N. S. Golosov ◽  
G. S. Golosova ◽  
L. E. Popov
Keyword(s):  
Phase Diagram ◽  
Ordered Phases

Magnetic structure and phase diagram of heavy fermion UPd2Ga3

1996 ◽  
Vol 223-224 ◽  
pp. 204-207 ◽  
Author(s):  
S.A.M Mentink ◽  
T.E Mason ◽  
S Süllow ◽  
G.J Nieuwenhuys ◽  
J.A Mydosh ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Magnetic Structure ◽  
Heavy Fermion

scholarly journals SUPERCONDUCTING PHASE TRANSITION IN THE NAMBU–JONA-LASINIO MODEL

2001 ◽  
Vol 16 (17) ◽  
pp. 1129-1138 ◽  
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.

scholarly journals (p,T,H) Phase Diagram of Heavy Fermion Systems: Some Systematics and Some Surprises from Ytterbium

2013 ◽  
Vol 26 (5) ◽  
pp. 1775-1780 ◽  
Author(s):  
D. Braithwaite ◽  
A. Fernandez-Pañella ◽  
E. Colombier ◽  
B. Salce ◽  
G. Knebel ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Heavy Fermion ◽  
Fermion Systems ◽  
Heavy Fermion Systems

HEAVY FERMIONS — THEIR MAGNETISM AND SUPERCONDUCTIVITY

1993 ◽  
Vol 07 (01n03) ◽  
pp. 2-8 ◽  
Author(s):  
F. STEGLICH ◽  
C. GEIBEL ◽  
A. LOIDL ◽  
G. SPARN ◽  
C. D. BREDL ◽  
...  
Keyword(s):  
Long Range ◽  
Heavy Fermion ◽  
Local Moment ◽  
Antiferromagnetic Order ◽  
Electron Systems ◽  
Correlated Electron Systems ◽  
Cooperative Phenomena ◽  
Correlated Electron ◽  
Highly Correlated ◽  
Heavy Fermion Superconductivity

Heavy-fermion compounds are ideally suited to study cooperative phenomena in highly correlated electron systems. We discuss local-moment magnetism and heavy-fermion band magnetism in the exemplary systems CeCu 2 Ge 2 and Ni-rich Ce(Cu 1− x Ni x )2 Ge 2, respectively. In addition, the coexistence of long-range antiferromagnetic order and heavy-fermion superconductivity in UM 2 Al 3 (M: Ni, Pd) will be addressed.

scholarly journals Bicritical Central Point of Ising Model Phase Diagram

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Yahia Boughaleb ◽  
Mohammed Nouredine ◽  
Mohamed Snina ◽  
Rachid Nassif ◽  
Mohamed Bennai
Keyword(s):  
Phase Diagram ◽  
Order Parameter ◽  
Present Model ◽  
Central Point ◽  
Square Lattice ◽  
Ordered Structures ◽  
Ordered Phases ◽  
Algebraic Order ◽  
Pure Phases ◽  
Model Phase

We deal with a 2D half occupied square lattice with repulsive interactions between first and second neighboring particles. Despite the intensive studies of the present model the central point of the phase diagram for which the ratio of the two interaction strengths is still open. In the present paper we show, using standard Monte Carlo calculations, that the situation corresponds to a phase of mixed ordered structures quantified by an “algebraic” order parameter defined as the sum of densities of the existing ordered clusters. The introduced grandeur also characterizes the transitions towards the known pure ordered phases for the other values of as mentioned by the agreement of our results with those of the literature. The computation of the Cowley short range order parameter against suggests that the central point is bicritical and is a state to cross when passing between the two pure phases.

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