Related papers: Phase transition and anomalous electronic behavior…
Local quantum phase transitions driven by Kondo correlations have been theoretically proposed in several magnetic nanosystems; however, clear experimental signatures are scant. Modeling a nickelocene molecule on a Cu(100) substrate as a…
Quantum chromodynamics (QCD) at finite temperature, $T$, and quark chemical potential, $\mu$, has a rich phase structure: at low $T$ and low $\mu$, the Nambu-Goldstone (NG) phase with nearly massless pions is realized by the dynamical…
The controversies about the structure of the true ground state of pseudorhombohedral compositions of Pb(ZrxTi1-x)O3 (PZT) are addressed using a 6% Sr2+ substituted sample with x=0.550. Sound velocity measurements reveal a phase transition…
2H-NbSe2 is the prototype and most frequently studied of the well-known transition metal dichalcogenide (TMDC) superconductors. Widely acknowledged to be a conventional superconductor, its transition temperature to the superconducting state…
To date, there has been no evidence for the macroscopic structural phase transition to the low temperature tetragonal structure (LTT) with a space group P42/ncm in high-TC cuprate of rare earth-free La2-xSrxCuO4 (LSCO). By investigating…
The inhomogeneous 3-Kelvin (3K) phase of the eutectic Sr2RuO4 with Ru inclusions nucleates superconductivity at the interface between Ru and Sr2RuO4. The structure of the interface state and its physical properties are examined here. Two…
The CuIr$_{2-x}$Ru$_x$Te$_4$ superconductors (with a $T_c$ around 2.8 K) can host charge-density waves, whose onset and interplay with superconductivity are not well known at a microscopic level. Here, we report a comprehensive study of the…
Thermal color superconducting phase transitions in high density three-flavor quark matter are investigated in the Ginzburg-Landau approach. Effects of nonzero strange quark mass, electric and color charge neutrality, and direct instantons…
We report $^{139}$La and $^{63}$Cu nuclear magnetic and quadrupole resonance (NMR/NQR) studies in an underdoped La$_{1.93}$Sr$_{0.07}$CuO$_4$ single crystal, focusing on the $^{139}$La NMR in the normal state. We demonstrate that the local…
We present the results of $^{75}$As nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR), and resistivity measurements in KFe$_2$As$_2$ under pressure ($p$). The temperature dependence of the NMR shift, nuclear spin-lattice…
We report on high-precision measurements of the temperature dependence of the plane-^63Cu NQR line frequency nu_Q(Cu2) and the linewidth in normal and superconducting ^16O and ^18O exchanged YBa_2Cu_4O_8. Whereas nu_Q(Cu2) passes T_c very…
$^{75}$As, $^{87}$Rb and $^{85}$Rb nuclear quadrupole resonance (NQR) and $^{87}$Rb nuclear magnetic resonance (NMR) measurements in RbFe$_2$As$_2$ iron-based superconductor are presented. We observe a marked broadening of $^{75}$As NQR…
We investigate the quantum phase transitions in strongly correlated electronic systems at $T=0^0K$ by the example of the 2D Hubbard model. The model for numerical calculations were formalized in terms of the integral equations previously…
The temperature dependencies of the resistivity for the superconducting ruthenocuprates of nominal compositions RuSr2GdCu2O8, Ru0.98Sr2GdCu2O8 and Ru0.5Sr2GdCu2.5O8-d were examined for the magnetic field dependent characteristics of the…
We generalize our previous model to an O(N) symmetric two-dimensional model which possesses chiral symmetry breaking and superconducting (Cooper pair condensates) phases at large-N. At zero temperature and density, the model can be solved…
Superconducting and antiferroquadrupolar (AFQ) transitions in a Pr-based compound PrRh2Zn20 have been found to occur simultaneously at Tc=TQ=0.06 K. The superconducting transition manifests itself by zero resistance and large diamagnetic…
The electronic and optical properties of low-dimensional semiconductors are typically quite different from those of their bulk counterparts. Yet, the optical gap of two-dimensional copper antimony disulfide (CuSbS$_2$) does not dramatically…
Understanding the complexities of electronic and magnetic ground states in solids is one of the main goals of solid-state physics. Materials with the canonical ThCr$_2$Si$_2$-type structure have proved particularly fruitful in this regards,…
We review the theories of a few quantum phase transitions in two-dimensional correlated electron systems and discuss their application to the cuprate high temperature superconductors. The coupled-ladder antiferromagnet displays a transition…
Nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) of Cu have been measured in a coupled spin dimers and chains compound Cu2Fe2Ge4O13. Cu NQR has also been measured in an isostructural material Cu2Sc2Ge4O13 including…