Reliable simulations of correlated quantum systems, including high-temperature
superconductors and frustrated magnets, are increasingly desired nowadays to further our …

The sign problem is a major obstacle in quantum Monte Carlo simulations for many-body
fermion systems. We examine this problem with a new perspective based on the Majorana …

We present a guiding principle for designing fermionic Hamiltonians and quantum Monte
Carlo (QMC) methods that are free from the infamous sign problem by exploiting the Lie …

We study the attractive SU (N) Hubbard model with particle-hole symmetry. The model is
defined on a bipartite lattice with the number of sites NA (NB) in the A (B) sublattice. We …

We study spinless fermions with nearest-neighbor repulsive interactions (tV model) on the
two-dimensional three-band Lieb lattice. At half-filling, the free electronic band structure …

We propose a new framework based on the concept of semigroup to understand the fermion
sign problem. By using properties of contraction semigroups, we obtain new sufficient …

We investigate the phase diagram of spinless fermions on a square lattice with nearest-
neighbor interaction, using the recently developed projective truncation approximation in …

We present a lattice model for superconducting fermions whose nearest-neighbour two-
body interactions are a Bardeen-Cooper-Schrieffer-type pairing on the hypercubic lattice …

Mathematical understanding of the origin of ferromagnetism is still incomplete and remains
an important research topic in mathematical physics. In this paper, we give a model …

A new framework for the reflection positivity, based on order-preserving operator
inequalities, is proposed. This framework is utilized to investigate one-dimensional fermion …