Related papers: Neutral-ionic phase transition : a thorough ab-ini…
Experimental nuclear level densities at excitation energies below the neutron threshold follow closely a constant-temperature shape. This dependence is unexpected and poorly understood. In this work, a fundamental explanation of the…
We have investigated the influence of Ca ions substitution on the structural and superconducting properties of (Nd1-xCax)(Ba1.6La0.4)Cu3Oz system. Magnetization, X-ray diffraction and neutron diffraction studies have been carried out on a…
Neutron powder diffraction studies of the crystal and magnetic structures of the magnetocaloric compound Mn1.1Fe0.9(P0.8Ge0.2) have been carried out as a function of temperature, applied magnetic field, and pressure. The data reveal that…
Phase transitions in a non-perturbative regime can be studied by ab initio Lattice Field Theory methods. The status and future research directions for LFT investigations of Quantum Chromo-Dynamics under extreme conditions are reviewed,…
We have studied the neutral-ionic transition in organic mixed-stack compounds. A unified model has been derived which, in limiting cases, is equivalent to the models proposed earlier, the donor-acceptor model and the ionic Hubbard model.…
Data from recent laser-shock experiments, density-functional theory (DFT) with molecular-dynamics (MD), and path-integral Monte Carlo (PIMC) simulations on carbon are compared with predictions from the neutral-pseudo-atom (NPA)+…
Background: Inelastic neutrino-nucleus scattering through the weak neutral-current plays important role in stellar environment where transport of neutrinos determine the rate of cooling. Since there are no direct experimental data on…
We report investigation of structural phase transitions in technologically important material sodium niobate as a function of temperature on heating over 300-1075 K. Our high resolution powder neutron diffraction data show variety of…
A string of trapped ions at zero temperature exhibits a structural phase transition to a zigzag structure, tuned by reducing the transverse trap potential or the interparticle distance. The transition is driven by transverse, short…
The formation of donor-acceptor complexes (DACs) between the electron donor Dibenzotetrathiafulvalene (DBTTF) and the acceptor Hexaaza\-triphenylene\-hexacarbo\-nitrile (HATCN) results in a new phase with a distinctly different crystal…
The neutron-neutron fusion process, $nn\to de\nu$, at very low neutron energies is studied in the framework of pionless effective field theory that incorporates dibaryon fields. The cross section and electron energy spectrum for this…
A study of QCD at non-zero chemical potential, mu, and temperature, T, is performed using the lattice technique. The transition temperature (between the confined and deconfined phases) is determined as a function of mu and is found to be in…
The phase transitions in a realistic system with triplet pairing, dense neutron matter, have been investigated. The spectrum of phases of the $^3P_2-^3F_2$ model, which adequately describes pairing in this system, is analytically…
We present an ab initio analysis for the ground-state properties of a correlated organic compound $\kappa$-(BEDT-TTF)2Cu(NCS)2. First, we derive an effective two-dimensional low-energy model from first principles, having short-ranged…
The martensitic {\alpha} --> {\omega} transition was investigated in Ti under hydrostatic pressure. The calculations were carried out using the density functional theory (DFT) framework in combination with the Birch-Murnaghan equation of…
Titanium nitride halides, TiNX (X = F, Cl, Br, I) in the {\alpha}-phase (orthorhombic) are exciting quasi two-dimensional (2D) electronic systems exhibiting a fascinating series of electronic ground states under different conditions.…
There are various methods for modeling phase transformations in materials science, including general classes of phase-field methods and reactive diffusion methodologies, which most importantly differ in their treatment of interface energy.…
This article is an overview of recent experimental and theoretical work on transport in phase-coherent hybrid nanostructures, with particular emphasis on dc electrical conduction. A summary of multiple scattering theory and the…
The rich phase diagram of bulk Pr$_{1-x}$Ca$_{x}$MnO$_3$ resulting in a high tunability of physical properties gave rise to various studies related to fundamental research as well as prospective applications of the material. Importantly, as…
CaFe$_2$As$_2$ has been synthesized and found to form in the tetragonal, ThCr$_2$Si$_2$ structure with lattice parameters $a = 3.912(68) \AA$ and $c = 11.667(45) \AA$. Upon cooling through 170 K, CaFe$_2$As$_2$ undergoes a first order,…