Lay summary
Quantum magnetism remains at the forefront of condensed matter physics. On one hand, it provides the ideal arena for developing and testing new fundamental concepts in solid-state and statistical physics, on the other hand it has a pivotal role in several classes of emerging materials with new electronic properties, e.g. the high-temperature superconducting cuprates and potentially solid state quantum information processing.This project combines two successful research programs within the Laboratory for Quantum Magnetism and its collaborators. A) Dimer Physics concern synthesis and experiments on materials hosting spin-1/2 pairs - the archetype of quantum entanglement - as building block for the occurrence of novel quantum phenomena and phases: Hard-core boson statistics, Bose-Einstein condensation, quantum phase transitions (QPTs) to new phases such as supersolids, and possible mechanisms to superconductivity. B) Dipolar Criticality is the experimental and theoretical investigation of quantum and thermal phase transitions, spin-glassiness and other phenomena in a family of insulating magnetic compounds, where dipolar forces between highly anisotropic rare-earth moments determine the effective model Hamiltonian.