Sign-problem-free Monte Carlo simulation of certain frustrated quantum magnets

Understand

We introduce a Quantum Monte Carlo (QMC) method which efficiently simulates in a sign-problem-free way a broad class of frustrated $S=1/2$ models with competing antiferromagnetic interactions.

• Our scheme uses the basis of total spin eigenstates of clusters of spins to avoid the severe sign problem faced by other QMC methods.
• We also flag important limitations of the new method, and comment on possibilities for further progress.