Polymorphism, which describes the occurrence of different lattice structures in a crystalline material, is a critical phenomenon in materials science and condensed matter physics. Recently, configuration disorder was compositionally engineered into single lattices, leading to the discovery of high-entropy alloys and high-entropy oxides. For these novel entropy-stabilized forms of crystalline ma...

We present a study of the critical phenomena around the quantum critical point in heavy-fermion systems. In the framework of the S = 1/2 Kondo lattice model, we introduce an extended decoupling scheme of the Kondo interaction which allows one to treat the spin fluctuations and the Kondo effect on an equal footing. The calculations, developed in a self-consistent one-loop approximation, lead to ...

We examine the percolation model by an approach involving lattice animals, divided according to their surface-area-to-volume ratio. Throughout, we work with the bond percolation model in Z. However, the results apply to the site or bond model on any infinite transitive amenable graph with inessential changes. For any given p ∈ (0, 1), two lattice animals with given size are equally likely to ar...

We apply a simple analytical criterion for locating critical temperatures to Potts models on square and triangular lattices. In the self-dual case, i. e. on the square lattice we reproduce known exact values of the critical temperature and derive the internal energy of the model at the critical point. For the Potts model on the triangular lattice we obtain very good numerical estimate of the cr...

Degenerate Hubbard models are studied using the Generalized-GutzwillerApproximation. It is found that the metal-insulator transition occurs at a finite correlation Uc when the average number of electrons per lattice site is an integer. The critical Uc depends sensitively on both the band degeneracy N and the filling x. A derivation is presented for the general expression of Uc(x,N) which reprod...

this work is a primary achievement in studying the co2 and n2–oil systems. to predict gas-liquid relative permeability curves, a shan-chen type multicomponent multiphase lattice boltzmann model for two-phase flow through 2d porous media is developed. periodic and bounce back boundary conditions are applied to the model with the guo scheme for the external body force (i.e., the pressure gradient...

The structure and morphology of ultrathin lattice matched CaF2 films of very few monolayers thickness, which were deposited on Si 111 substrates by molecular-beam epitaxy, have been studied in situ by synchrotron based grazing incidence x-ray diffraction. Even for the thinnest investigated film of three monolayers thickness, the in-plane structure of the CaF2 film is determined by a lateral sep...

We study the critical phenomena of the hard-sphere lattice gas on the simple cubic lattice with nearest neighbour exclusion by the Monte Carlo method. We get the critical exponents, β/ν = 0.313(9) and γ/ν = 2.37(2), where β is the critical exponent for the staggered density, γ for the staggered compressibility, and ν for the correlation length.