相关论文: Relevance of electron-lattice coupling in cuprates…
The oxygen-isotope (^16O/^18O) effect (OIE) on the in-plane penetration depth $\lambda_{ab} (0)$ in underdoped Y_{1-x}Pr_xBa_2Cu_3O_{7-delta} was studied by muon-spin rotation. A pronounced OIE on $\lambda_{ab}^{-2}(0)$ was observed with a…
We have studied the oxygen-isotope effects on T_{c} and in-plane penetration depth \lambda_{ab}(0) in an optimally doped 3-layer cuprate Bi_{1.6}Pb_{0.4}Sr_{2}Ca_{2}Cu_{3}O_{10+y} (T_{c} \sim 107 K). We find a small oxygen-isotope effect on…
The electron-phonon interaction is of central importance for the electrical and thermal properties of solids, and its influence on superconductivity, colossal magnetoresistance, and other many-body phenomena in correlated-electron materials…
We have studied the oxygen-isotope effect on the superconducting transition temperature $T_{c}$ in overdoped Y$_{1-x}$Ca$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-\delta}$ with $x$ = 0.10, 0.20, and 0.25. We find the oxygen-isotope exponent $\alpha_{O}$…
High resolution resonant inelastic x-ray scattering has been performed to reveal the role of lattice-coupling in a family of quasi-1D insulating cuprates, Ca$_{2+5x}$Y$_{2-5x}$Cu$_5$O$_{10}$. Site-dependent low energy excitations arising…
The oxygen-isotope (^{16}O/^{18}O) effect (OIE) on the in-plane magnetic penetration depth \lambda_{ab}(0) in optimally-doped YBa_2Cu_3O_{7-\delta} and La_{1.85}Sr_{0.15}CuO_4, and in slightly underdoped YBa_2Cu_4O_8 and…
The mechanism of electron pairing in high-temperature superconductors is still the subject of intense debate. Here, we provide direct evidence of the role of structural dynamics, with selective atomic motions (buckling of copper-oxygen…
The attempt to understand cuprate superconductors is complicated by the presence of multiple strong interactions. While many believe that antiferromagnetism is important for the superconductivity, there has been revived interest in the role…
The oxygen-isotope (^{16}O/^{18}O) effect (OIE) on the zero-temperature superconducting energy gap \Delta_0 was studied for a series of Y_{1-x}Pr_xBa_2Cu_3O_{7-\delta} samples (0.0\leq x\leq0.45). The OIE on \Delta_0 was found to scale with…
Based on recently proposed anti-ferromagnetic spin fluctuation exchange models for $d_{x^2-y^2}$-superconductors, we show that coupling to harmonic phonons {\it{cannot}} account for the observed isotope effect in the cuprate high-$T_c$…
X-ray absorption spectroscopy (XAS) and high resolution X-ray diffraction are combined to study the interplay between electronic and lattice structures in controlling the superconductivity in cuprates with a model charge-compensated…
The oxygen isotope ($^{16}$O/$^{18}$O) effect (OIE) on the pseudogap (charge-stripe ordering) temperature $T^{\ast}$ is investigated for the cuprate superconductor La$_{2-x}$Sr$_{x}$CuO$_{4}$ as a function of doping $x$ by means of x-ray…
From the observed oxygen-isotope shift of the mid-infrared two-magnon absorption peak of YBa$_{2}$Cu$_{3}$O$_{6}$, we evaluate the oxygen-isotope effect on the in-plane antiferromagnetic exchange energy $J$. The exchange energy $J$ in…
The oxygen isotope effect on the superconductivity, stripe phase and structure transition is systematically investigated in La$_{1.6-x}$Nd$_{0.4}$Sr$_{x}$CuO$_4$ with static stripe phase. Substitution of $^{16}$O by $^{18}$O leads to a…
A recent angle resolved photoelectron spectroscopy (ARPES) study by Douglas et al. \cite {dessau-comment} on oxygen isotope exchanged Bi_2Sr_2CaCu_2O$_{8+\delta}$ superconductors reported an absence of isotope effect at optimal doping,…
Systematic Raman studies on several cuprates (YBa$_{\rm 2}$Cu$_{\rm 3}$O$_{\rm x}$, YBa$_{\rm 2}$Cu$_{\rm 4}$O$_{\rm 8}$ or Bi$_{\rm 2}$Sr$_{\rm 2}$CaCu$_{\rm 2}$O$_{\rm 8}$) have shown that at optimal doping the compounds are at the edge…
It is shown that the empirical relations between transition temperature, normal state conductivity linearly extrapolated to the value at the transition temperature, zero temperature penetration depths, etc., as observed in a rich variety of…
We identify dd-excitations in the quasi-one dimensional compound Ca$_2$Y$_2$Cu$_5$O$_{10}$ using resonant inelastic x-ray scattering. By tuning across the Cu L$_3$-edge, we observe abrupt shifts in the dd-peak positions as a function of…
Granularity, anisotropy, local lattice distortions and their dependence on dopant concentration appear to be present in all cuprate superconductors, interwoven with the microscopic mechanisms responsible for superconductivity. Here we…
An understanding of spin excitations in cuprates is essential since the mechanism of high-T$_C$ superconductivity might be linked to spin fluctuations. Band calculations for long "1-dimensional" unit cells of La$_2$CuO$_4$ show that the…