Related papers: Ab Initio Study of the Structural Phase Transition…
Cubic Pm-3n Nb3Sn0.92 superconductor (Tc ~ 16 K) was found to exhibit tetragonal instabilities at the superconducting state (T = 10 K). These instabilities are manifested through the appearance of reflections which are forbidden in the…
The average and local structures of the (PbTe)1-x(PbS)x system of thermoelectric materials has been studied using the Rietveld and atomic pair distribution function (PDF) methods. Samples with 0:25 < x are macroscopically phase separated.…
The recently reported gate-tunable superconductivity in monolayer WTe$_2$ [Science 362, 922 (2018); Science 362, 926 (2018); Nat. Phys. 20, 269 (2024); PRR 7, 013224 (2025)] exhibits several striking anomalies beyond the standard paradigm,…
We have investigated the Pb-substitution effect on the superconductivity of NaCl-type In1-xPbxTe samples obtained using high-pressure synthesis. Polycrystalline samples with x = 0-0.8 were obtained, and the lattice parameter systematically…
We show that the quasi-skutterudite superconductor Sr_3Ir_4Sn_{13} undergoes a structural transition from a simple cubic parent structure, the I-phase, to a superlattice variant, the I'-phase, which has a lattice parameter twice that of the…
We consider the thermodynamics of a homogeneous superfluid dilute Bose gas in the presence of weak quenched disorder. Following the zero-temperature approach of Huang and Meng, we diagonalize the Hamiltonian of a dilute Bose gas in an…
We report a novel high pressure structural sequence for the functionally graded thermoelectric, narrow band gap semiconductor AgSbTe$_{2}$, using angle dispersive x-ray diffraction in a diamond anvil cell with synchrotron radiation at room…
Single crystals of XPt$_{5}$P (X = Al, Ga, and In) were grown from a Pt-P solution at high temperatures, and ambient-pressure measurements of temperature-dependent magnetization, resistivity, and X-ray diffraction were made. Also, the…
Phase separation has been observed by several different experiments and it is believed to be closely related with the physics of cuprates but its exactly role is not yet well known. We propose that the onset of pseudogap phenomenon or the…
In this paper we develop a gapless theory of BEC which can be applied to both trapped and homogeneous gases at zero and finite temperature. The many-body Hamiltonian for the system is written in a form which is approximately quadratic with…
Transient responses of the electronic excitation and coherent soft phonon are investigated both above and below the ferroelectric phase transition temperature T$_{c}$ in Pb$_{1-x}$Ge$_{x}$Te by using an optical pump-probe technique. The…
Configurationally disordered crystalline boron carbide, B$_{4}$C, is studied using first-principles calculations. We investigate both dilute and high concentrations of carbon-boron substitutional defects. For the latter purpose, we suggest…
We study the superconducting transition temperature and the electronic properties of the metallic phase of $\kappa$-type (BEDT-TTF)$_2$X which shows unconventional properties in experiments, on the basis of the third order perturbation…
On the basis of the recently proposed self-consistent theory of metal- insulator transition in strongly disordered systems, taking into account interaction effects, we study transition temperature $T_{c}$ suppression in disordered…
High-pressure synthesis techniques have allowed for the growth of samples on the indium-rich side of (Pb,In)Te, which have increased superconducting transition temperatures compared to lead-rich compounds. In this study we present…
Using a finite-temperature Path Integral Monte Carlo simulation (PIMC) method and finite-size scaling, we have investigated the interaction-induced shift of the phase transition temperature for Bose-Einstein condensation of homogeneous…
Predicting the superconducting transition temperature ($T_c$) from crystal structure and composition remains a central challenge in condensed-matter physics, reflecting the absence of a broadly predictive framework connecting microscopic…
The three-dimensional purely plaquette gonihedric Ising model and its dual are investigated to resolve inconsistencies in the literature for the values of the inverse transition temperature of the very strong temperature-driven first-order…
Recent discovery of topological superconductors (TSCs) has sparked enormous interest. Realization of TSC requires a delicate tuning of multiple microscopic parameters, which remains a great challenge. Here, we develop a first-principles…
SnTe, an archetypical topological crystalline insulator, often shows a transition from a highly symmetric cubic phase to a rhombohedral structure at low temperatures. In order to achieve the highly symmetric cubic phase at low temperatures…