Related papers: Negative thermal expansion near two structural qua…
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…
We discuss quantum phase transition by an exactly solvable model in the dual gravity setup. By considering the effect of the scalar condensation on the fermion spectrum near the quantum critical point(QCP), we find that there is a…
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…
The origin of negative thermal expansion (NTE) in the bond frustrated ZnCr2Se4 has been explored. ESR and FTIR document an ideal paramagnetic state above 100 K, below which ferromagnetic clusters coexist with the paramagnetic state down to…
We investigate detailed lattice dynamics of copper halides CuX (X=Cl, Br, I) using neutron inelastic scattering measurements and ab-initio calculations aimed at a comparative study of their thermal expansion behavior. We identify the low…
The upper critical field $H_{c2} $, the field $H_{c3}$ for nucleation of the surface superconductivity, and the thermodynamic $H_c $ are evaluated within the weak-coupling theory for the isotropic s-wave case and arbitrary transport and…
The uniaxial negative thermal expansion in pentacene crystals along $a$ is a particularity in the series of the oligoacenes, and exeptionally large for a crystalline solid. Full x-ray structure analysis from 120 K to 413 K reveals that the…
Magnetoresistivity measurements with fine tuning of the field direction on high quality single crystals of the ferromagnetic superconductor UCoGe show anomalous anisotropy of the upper critical field H_c2. H_c2 for H // b-axis (H_c2^b) in…
We report high-resolution neutron powder diffraction on Sr0.61Ba0.39Nb2O6, SBN61, in the temperature range 15-500 K. The results indicate that the low-temperature anomalies (T<100K) observed in the dielectric dispersion are due to small…
We report the single-crystal X-ray analysis and magnetic properties of a new double-layered perovskite antiferromagnet, Cs$_3$Cu$_2$Cl$_4$Br$_3$. This structure is composed of Cu$_2$Cl$_4$Br$_3$ double layers with elongated CuCl$_4$Br$_2$…
Quantum criticality arises when a macroscopic phase of matter undergoes a continuous transformation at zero temperature. While the collective fluctuations at quantum-critical points are being increasingly recognized as playing an important…
We report low-temperature thermal-expansion measurements on single crystals of the {\it layered} heavy fermion system \cri ($0.3\leq x \leq 0.6$) and compare it with a previous study on the related {\it cubic} system \ci [R. K\"{u}chler…
Structural disorder is common in metal-halide perovskites and important for understanding the functional properties of these materials. First-principles methods can address structure variation on the atomistic scale, but they are often…
Motivated by the experimental synthesis of two-dimensional (2D) perovskite materials, we study the stability of 2D SrTiO$_3$ from first principles. We find that the TiO$_6$ octahedral rotations emerge in 2D SrTiO$_3$ with a rotation angle…
The family of the superconducting quasi-skutterudites (Ca$_x$Sr$_{1-x}$)$_3$Rh$_4$Sn$_{13}$ features a structural quantum critical point at $x_c=0.9$, around which a dome-shaped variation of the superconducting transition temperature $T_c$…
The layered perovskite Sr$_2$RuO$_4$ serves as a model material of the two-dimensional (2D) Fermi liquid but also exhibits various emergent phenomena including the non-Fermi-liquid (NFL) behavior under external perturbations such as…
One-dimensional organo-metal halide Perovskite (CH3NH3PbI3) nanorods whose diameter and length are dictated by the inner size of porous silicon nanotube templates have been grown, characterized and compared to bulk perovskites in the form…
Bulk Scandium trifluoride ($\mathrm{ScF_3}$) is known for a pronounced negative thermal expansion (NTE) over a wide range of temperature, from $10~\mathrm{K}~\text{to}~ 1100~\mathrm{K}$. The structure of $\mathrm{ScF_3}$ can be described as…
The critical behavior at the special surface transition and crossover bevavior from special to ordinary surface transition in semi-infinite n-component anisotropic cubic models are investigated by applying the field theoretic approach…
We discovered the enhancement of superconducting transition temperature, Tc, in yttrium sesquicarbide system with the maximum Tc of Tc=18K and their superconducting properties were discussed. The crystal structure of Y2C3 is the…