Related papers: Correlation length in cuprates deduced from the im…
We present a theory of magnetic (Ni) and nonmagnetic (Zn) impurities substituted into planar Cu sites in the normal state of underdoped cuprates exhibiting a spin gap. Both types of impurities induce magnetic moments on neighboring Cu…
We present a 31P NMR study of the coupled spin 1/2 ladder compound BiCu2PO6. In the pure material, intrinsic susceptibility and dynamics show a spin gap of about . Substitution of non magnetic Zn or magnetic Ni impurity at Cu site induces a…
Substitutional impurities in the CuO2 planes of the cuprates allow us to probe the electronic properties of the host material. The pseudo-gap in the underdoped regime is unmodified far from the impurities even though Tc is greatly reduced.…
We present a theory of magnetic (S=1) Ni and nonmagnetic Zn impurities in underdoped cuprates. Both types of impurities are shown to induce S=1/2 moments on Cu sites in the proximity of the impurity, a process which is intimately related to…
Planar oxygen nuclear magnetic resonance (NMR) relaxation and shift data from all cuprate superconductors available in the literature are analyzed. They reveal a temperature independent pseudogap at the Fermi surface, which increases with…
The $S=1/2$ antiferromagnetic Heisenberg spin chain compound Sr$_2$CuO$_3$ doped with $1 \%$ and $2 \%$ of Ni impurities has been studied by means of $^{63}$Cu nuclear magnetic resonance. A strong decrease of the spin-lattice relaxation…
The {}^{17}O NMR spectra of Bi_2Sr_2CaCu_2O$_{8+\delta}$ (Bi-2212) single crystals were measured in the temperature range from 4 K to 200 K and magnetic fields from 3 to 29 T, reported here principally at 8 T. The NMR linewidth of the…
We report $^{63,65}$Cu NQR measurements on slightly underdoped NdBa$_{2}$Cu$_{3}$O$_{6+y}$ single crystals heavily doped by Ni and Zn impurities. Owing to the impurity doping superconductivity is fully suppressed in both cases. The Ni…
The influence of magnetic Ni and non-magnetic Zn impurities on the normal state pseudogap (PG) in the c-axis optical conductivity of NdBa$_{2}$\{Cu$% _{1-y}$(Ni,Zn)$_{y}\}_{3}$O$_{7-\delta}$ crystals was studied by spectral ellipsometry. We…
Understanding high-temperature superconductivity requires a prior knowledge of the nature of the enigmatic pseudogap metallic state, out of which the superconducting state condenses. In addition to the electronic orders involving charge…
We study a magnetic impurity embedded in a correlated electron system using the density-matrix renormalization group method. The correlated electron system is described by the one-dimensional Hubbard model. At half filling, we confirm that…
It is now well established that Zn doping of high-$T_C$ cuprates reduces their $T_C$ and triggers the appearence of a spin glass phase. In this context, we have solved exactly the problem of N non magnetic impurities in the staggered flux…
New phases with broken discrete Ising symmetries are uncovered in quantum materials with strong electronic correlations. The two-leg ladder cuprate \textbf{$Sr_{14-x}Ca_{x}Cu_{24}O_{41}$} hosts a very rich phase diagram where, upon hole…
Nuclear magnetic resonance (NMR) of planar oxygen, with its family independent phenomenology, is ideally suited to probe the nature of the quantum matter of superconducting cuprates. Here, with new experiments on La$_{2-x}$Sr$_x$CuO$_4$, in…
We examine the low-temperature magnetic properties of moderately doped LaSrCuO paying particular attention to the spin-glass (SG) phase and the C-IC transition as they are affected by Sr impurity disorder. New measurements of the…
The loop-current state discovered in under-doped cuprates is characterized by a vector ${\bf \Omega}$ which has four possible orientations which correspond to different domains of order in a perfect sample. Since translational symmetry…
We determine the magnetic phase diagram for the YBa$_2$Cu$_3$O$_{6+x}$ and La$_{2-x}$Sr$_x$CuO$_4$ systems from various NMR experiments. We discuss the possible interpretation of NMR and neutron scattering experiments in these systems in…
An understanding of the normal state in the high-temperature superconducting cuprates is crucial to the ultimate understanding of the long-standing problem of the origin of the superconductivity itself. This so-called strange metal state is…
The magnetic polarization induced by nonmagnetic impurities such as Zn in high Tc cuprate compounds is studied by the variational Monte Carlo simulation. The variational wave function is constructed from the eigenstates obtained from…
Despite decades of intense researches, the enigmatic pseudo-gap (PG) phase of superconducting cuprates remains an unsolved mystery. In the last 15 years, various symmetry breakings in the PG state have been discovered, spanning an…