Preempting fermion sign problem: Unveiling quantum criticality through nonequilibrium dynamics in imaginary time

The notorious fermion sign problem, arising from fermion statistics, presents a fundamental obstacle to the numerical simulation of quantum many-body systems. Here, we introduce an innovative framework that circumvents the sign problem in the studies of quantum criticality and the associated phases by leveraging imaginary-time nonequilibrium critical dynamics. We demonstrate that the critical properties can be accurately determined from the system’s short-time relaxation, a regime where the sign problem remains manageable for quantum Monte-Carlo (QMC) simulations. After validating this approach on two benchmark fermionic models, we apply it to the sign-problematic Hubbard model hosting SU(3)-symmetric Dirac fermions. We present the first numerically exact characterization of its quantum phase diagram, revealing a continuous transition between a Dirac semi-metal and a novel antiferromagnetic phase, which belongs to a new universality class, distinct from the previously known Gross-Neveu ..., , , ## Preempting fermion sign problem: Unveiling quantum criticality through nonequilibrium dynamics in imaginary time

Dryad DOI: https://doi.org/10.5061/dryad.dncjsxmch

This repository contains the raw numerical data underlying all figures in the main text and supplementary materials of the paper \"Preempting Fermion Sign Problem: Unveiling Quantum Criticality through Nonequilibrium Dynamics in Imaginary Time\" (Science Advances; see also arXiv:2410.18854). The dataset is organized to mirror the figure numbering and panel structure used in the manuscript for straightforward cross-referencing and reuse.

## Overview

* Scope: Raw numerical data for every plotted figure in the main text and Supplementary Materials (SM).
* Organization: `main-text.zip` holds main-text figure data; `supplementary-materials.zip` holds SM data organized by section.
After unzipping these archives, you obtain the `main-text/` and `supplementary-materials/` directories described below.
* Formats:
* `.xlsx`: Ex...