Related papers: Bulk charge density wave and electron-phonon coupl…
Charge modulations have been widely observed in cuprates, suggesting their centrality for understanding the high-$T_c$ superconductivity in these materials. However, the dimensionality of these modulations remains controversial, including…
In previous reports a structural transition from a cubic phase of Yb$_3$Rh$_4$Sn$_{13}$ - type to the superlattice variant has been reported at $\sim160$ K for a series of skutterudite-related Ce$_3$M$_4$Sn$_{13}$ compounds, where M=Co, Ru…
We find unknown $s$- and $d$-wave amplitudes of the recently discovered charge density wave (CDW) in underdoped cuprates. To do so we perform a combined analysis of experimental data for ortho-II YBa$_2$Cu$_3$O$_{y}$. The analysis includes…
While the conducting CuO$_2$ planes in cuprate superconductors have been widely recognized as a crucial component in producing high superconducting $T_\text{c}$, recent experimental and theoretical studies on…
Charge-density-wave (CDW) order in correlated metals originates in a peaked electronic susceptibility at a finite wavevector $\mathbf Q_0$, set either by Fermi-surface features (nesting or saddle-point singularities) or by momentum-resolved…
Overdoped high-temperature cuprate superconductors have been widely believed to be described by the physics of d-wave BCS-like superconductivity. However, recent measurements indicate that as the doping is increased, the superfluid density…
We use polarized magneto-Raman scattering to study purely electronic excitations and the electron-phonon coupling in bulk graphite. At a temperature of 4.2 K and in magnetic fields up to 28 T we observe $K$-point electronic excitations…
An incommensurate charge density wave (CDW) is a periodic modulation of charge that breaks translational symmetry incongruently with the underlying lattice. Its low-energy excitations, the phason, are collective, gapless phase fluctuations.…
Purely local experimental probes of many copper oxide superconductors show that their electronic states are inhomogeneous in real space. For example, scanning tunneling spectroscopic (STS) imaging shows strong variations in real space, and…
We investigate resonant inelastic X-ray scattering (RIXS) at the O $K$-edge in insulating cuprates by means of three methods: cluster perturbation theory (CPT), Hartree--Fock approximation (HFA) and exact diagonalization (ED) method. We…
We use resonant inelastic x-ray scattering (RIXS) at the Cu L$_3$ edge to measure the charge and spin excitations in the "half-stuffed" Cu--O planes of the cuprate antiferromagnet Ba$_2$Cu$_3$O$_4$Cl$_2$. The RIXS line shape reveals…
The subject of the present study is the double-layer square-lattice system with the intralayer phonon modulations. We investigate the superconducting and excitonic pairings, as well as their coexistence, as functions of various physical…
The trivalent alkali fullerides A$_3$C$_{60}$, where C$_{60}$ are a well established family of molecular superconductors. The electron pairing has s-wave symmetry and is due to standard electron-phonon coupling, in particular by Jahn-Teller…
The interplay between electron-electron correlations and disorder has been a central theme of condensed matter physics over the last several decades, with particular interest in the possibility that interactions might cause delocalization…
The polaron binding energy E_{p} in undoped parent cuprates has been determined to be about 1.0 eV from the unconventional oxygen-isotope effect on the antiferromagnetic ordering temperature. The deduced value of E_{p} is in quantitative…
Charge, spin, as well as lattice instabilities are investigated in isolated or weakly coupled chains of correlated electrons at quarter-filling. Our analysis is based on extended Hubbard models including nearest neighbor repulsion and…
We investigate a model where superconducting electrons are coupled to a frequency dependent charge-density wave (CDW) order parameter Delta(w). Our approach can reconcile the simultaneous existence of low energy Bogoljubov quasiparticles…
Resonant inelastic x-ray scattering at the N K edge reveals clearly resolved harmonics of the anion plane vibrations in the kappa-(BEDT-TTF)2Cu2(CN)3 spin-liquid insulator. Tuning the incoming light energy at the K edge of two distinct N…
We adopt a $t_1-t_2-t_3-J-G$ model for explanation of $x=1/8$ anomaly in La$_{2-x}$Sr$_x$CuO$_4$ family compound. The calculated charge susceptibility shows a maximum near $(\pi,\pi)$ at intermediate temperatures and near $(\pi,\pi/2)$ as…
A resonant inelastic x-ray scattering study of the electronic structure of the semiconductor cuprous oxide, $\rm Cu_2O$, is reported. When the incident x-ray energy is tuned to the Cu K-absorption edge, large enhancements of the spectral…