Related papers: Electronic crossover suggested by Raman scattering…
The reflectance of high-quality, unpolished single crystals of YBa_2Cu_3O_{6+x}, for the doping range x=0.50 -> 0.95, has been measured with radiation polarized along the c axis from approx 50 cm^{-1} to 5000 cm^{-1} between 10 K and 300 K.…
We report Raman measurements on Bi2Sr2CaCu2O8+d single crystals which allow us to quantitavely evaluate the doping dependence of the density of Cooper pairs in the superconducting state. We show that the drastic loss of Cooper pairs in the…
Mechanism of unconventional superconductivity is still unknown even if more than 25 years have been passed since the discovery of high-Tc cuprate superconductors by J.G. Bednorz and K. A. Muller. Here, we explore the cuprate phase diagram…
We study the Raman response, for $B_{1g}$ and $B_{2g}$ light-polarization symmetries, of the charge density wave phase appearing in the underdoped region of cuprate superconductors. We show that the $B_{2g}$ response provides a distinctive…
Resonant magnetic modes with odd and even symmetries were studied by inelastic neutron scattering experiments in the bilayer high-$T_c$ superconductor $\rm Y_{1-x}Ca_{x}Ba_2Cu_3O_{6+y}$ over a wide doping range. The threshold of the spin…
The thermodynamics of the superconducting transition is studied as a function of doping using high-resolution expansivity data of YBa2Cu3Ox single crystals and Monte-Carlo simulations of the anisotropic 3D-XY model. We directly show that Tc…
We report the Raman scattering measurements on the triple layer Bi2Sr2Ca2Cu3O10 (Bi2223) crystals of four different doping levels from slightly overdoped to strongly underdoped regimes. We observed a double pair-breaking peak in the…
The electron dynamics in the normal state of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ is studied by inelastic light scattering over a wide range of doping. A strong anisotropy of the electron relaxation is found which cannot be explained by…
We present details of carrier properties in high quality ${\rm Ba(Fe_{1-x}Co_{x})_2As_2}$ single crystals obtained from electronic Raman scattering. The experiments indicate a strong band and momentum anisotropy of the electron dynamics…
We report a fine tuned doping study of strongly overdoped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals using electronic Raman scattering. Combined with theoretical calculations, we show that the doping, at which the normal state…
We report a neutron scattering study of the spin excitation spectrum in the superconducting state of slightly overdoped Bi2Sr2CaCu2O8+d system (Tc=87 K). We focus on the dispersion of the resonance peak in the superconducting state that is…
We investigate the electronic background as well as the O2-O3 mode at 330 cm^-1 of highly doped YbBa2Cu3O7-delta in B1g symmetry. Above the critical temperature Tc the spectra consist of an almost constant electronic background and…
We report pressure tuned Raman and x-ray diffraction data of Bi1.98Sr2.06Y0.68Cu2O8 revealing a critical pressure at 21 GPa with anomalies in six physical quantities: electronic Raman background, electron-phonon coupling, spectral weight…
We report on a study of the electromagnetic response of three different families of high-T_c superconductors that in combination allowed us to cover the whole doping range from under- to overdoped. The discussion is focused on the ab-plane…
Temperature and doping dependent tunneling spectroscopy on $Bi_2Sr_2CaCu_2O_{8+\delta}$ single crystals has been investigated by using break-junction technique. The results provide direct evidence that the pseudogap persists into heavily…
We show that the novel features observed in Raman experiments on optimally doped and underdoped Bi-2212 compounds in $B_{1g}$ geometry can be explained by a strong fermionic self-energy due to the interaction with spin fluctuations. We…
In this paper we examine the effects of electron-hole asymmetry as a consequence of strong correlations on the electronic Raman scattering in the normal state of copper oxide high temperature superconductors. Using determinant quantum Monte…
Many complex electronic systems exhibit so-called pseudogaps, which are poorly-understood suppression of low-energy spectral intensity in the absence of an obvious gap-inducing symmetry. Here we investigate the superconductor…
A structural phase transformation in the CuO_2 planes of YBa_2Cu_3O_x has been observed at the onset of the overdoped regime, x=6.95. We have measured as a function of x the dimpling in the CuO_2 planes by EXAFS, and the O2,3 in-phase…
Electron-boson coupling plays a key role in superconductivity for many systems. However, in copper-based high-temperature ($T_c$) superconductors, its relation to superconductivity remains controversial despite strong spectroscopic…