The performance of materials such as steels, their high strength and formability, is based on
an impressive variety of competing mechanisms on the microscopic/atomic scale (eg …

We discuss designer Hamiltonians—lattice models tailored to be free from sign problems
(“de-signed”) when simulated with quantum Monte Carlo (QMC) methods but which still host …

The “sign problem”(SP) is a fundamental limitation to simulations of strongly correlated
matter. It is often argued that the SP is not intrinsic to the physics of particular Hamiltonians …

The deconfined quantum critical point (DQCP) represents a paradigm shift in quantum
matter studies, presenting a “beyond Landau” scenario for order-order transitions. Its …

These lecture notes introduce quantum spin systems and several computational methods for
studying their ground‐state and finite‐temperature properties. Symmetry‐breaking and …

We introduce the concept of directed loops in stochastic series expansion and path-integral
quantum Monte Carlo methods. Using the detailed balance rules for directed loops, we …

A review of the loop algorithm, its generalizations, and its relation to some other Monte Carlo
techniques is given. The loop algorithm is a quantum Monte Carlo procedure that employs …

The antiferromagnetic to valence-bond-solid phase transition in the two-dimensional JQ
model (an S= 1/2 Heisenberg model with four-spin interactions) is studied using large-scale …

We study two-dimensional Heisenberg antiferromagnets with additional multispin
interactions which can drive the system into a valence-bond-solid state. For standard SU (2) …

Quantum Monte Carlo (QMC) methods are the gold standard for studying equilibrium
properties of quantum many-body systems. However, in many interesting situations, QMC …