Although condensed matter systems usually do not have higher-form symmetries, we show
that, unlike 0-form symmetry, higher-form symmetries can emerge as exact symmetries at …

Magnetic skyrmions are nanoscale topological textures that have been recently observed in
different families of quantum magnets. These objects are called CP1 skyrmions because …

Quantum magnets admit more than one classical limit and N-level systems with strong
single-ion anisotropy are expected to be described by a classical approximation based on …

We establish, in the spirit of the Lieb-Schultz-Mattis theorem, lower bounds on the spectral
degeneracy of quantum systems with higher (gaugelike) symmetries with rather generic …

We provide a quantitative characterization of generic weakly first-order thermal phase
transitions out of planar spin-nematic states in three-dimensional spin-one quantum …

We present a high-field study of the strongly anisotropic easy-plane square lattice S= 2
quantum magnet Ba 2 FeSi 2 O 7. This compound is a rare high-spin antiferromagnetic …

The work considers a model of charged" semi-hard-core" bosons on a square lattice with a
possible filling number at each node, ranging from 0 to 2. Temperature phase diagrams of …

The realization of a computer that exploits quantum-rather than classical-principles
represents a formidable scientific and technological challenge. Today, superconducting …

In this thesis, we study different quantum Heisenberg antiferromagnets (AFMs) by means of
unbiased large-scale quantum Monte Carlo (QMC) simulations. First, we consider the spin-1 …