In materials with strong local Coulomb interactions, simple defects such as atomic
substitutions strongly affect both macroscopic and local properties of the system. A …

An overview of one-and two-dimensional quantum spin systems based on transition-metal
oxides and halides of current interest is given, such as spin-Peierls, spin-dimer …

We analyze the effect of quenched disorder on spin-1/2 quantum magnets in which
magnetic frustration promotes the formation of local singlets. Our results include a theory for …

In recent years, the study of ladder materials has developed into a well-established area of
research within the general context of strongly correlated electrons. This effort has been …

A novel cuprate Volborthite, Cu3V2O7 (OH) 2Á2H2O, containing an S-1/2 (Cu2þ spin)
kagomélike lattice is studied by magnetic susceptibility, specific heat, and 51V NMR …

The theoretical description of the anomalous properties of the pseudogap phase in the
underdoped region of the cuprate phase diagram lags behind the progress in spectroscopic …

Magnetic susceptibility, high-field magnetization, and inelastic neutron scattering
experiments are used to study the magnetic properties of a new S= 1 quasi-one-dimensional …

The study of randomness in low-dimensional quantum antiferromagnets is at the forefront of
research in the field of strongly correlated electron systems, yet there have been relatively …

We report measurements of the specific heat and the thermal conductivity of the model
Heisenberg spin-1/2 chain cuprate Sr 2 CuO 3 at low temperatures. In addition to a nearly …

We compare the effects of in-plane nonmagnetic Li+ and Zn 2+ impurities on the normal
state of high-T c cuprates. 89 Y NMR shows that the extra hole introduced by Li is not …