On a large class of lattices (such as the sawtooth chain, the kagome and the pyrochlore
lattices), the quantum Heisenberg and the repulsive Hubbard models may host a completely …

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 …

In combination with Laughlin's treatment of the quantized Hall conductivity, the Lieb-Schultz-
Mattis argument is extended to quantum many-particle systems (including quantum spin …

For a class of frustrated spin lattices including the Kagomé lattice we construct exact
eigenstates consisting of several independent, localized one-magnon states and argue that …

In magnetism, of which molecular magnetism is a part, the term frustration is used rather
sloppily. Sometimes one gains the impression that if the reason for some phenomenon is not …

Publisher Summary This chapter discusses percolation theory as well as spin-glass
phenomena, the former of which is used to understand subjects as diverse as fluid flow in …

For the paradigmatic frustrated spin-half Heisenberg antiferromagnet on the kagome lattice
we performed large-scale numerical investigations of thermodynamic functions by means of …

We review recent developments regarding the quantum dynamics and many-body physics
with light, in superconducting circuits and Josephson analogues, by analogy with atomic …

The authors discuss concepts used by them and others for studying high temperature
superconductivity. These shed some light on basic questions. Suggestions are presented …

A major constraint on experimental studies of geometrically frustrated magnets (GFMs) is the
availability of suitable samples that provide tangible models to inspire or test theory. Most …