Wilson Fermions Enable Quantum Simulations of Topological Phases

Researchers at the Helmholtz Institute, alongside collaborators from institutions including UCLA, MIT and Tsinghua University, have charted a path toward stable topological phases within quantum systems. The team’s work focuses on (2+1)D quantum electrodynamics (QED3) with Wilson fermions, a notoriously difficult area for quantum simulation due to its inherent complexity. This research demonstrates why staggered fermions cannot induce topological phases in this system, while Wilson fermions can support phases like Chern insulators and quantum spin Hall states, and further uncovers a detailed phase diagram for the two-flavor Wilson fermion model. These findings resolve ambiguities in existing theoretical frameworks and lay groundwork for future quantum simulations on emerging computing platforms. Wilson fermions, a specific type of fermion discretization, demonstrably enable the emergence of topological phases in (2+1)-dimensional quantum electrodynamics (QED3), a finding that resolves long-standing ambiguities in Hamiltonian formulations of lattice field theories. Unlike their staggered fermion counterparts, Wilson fermions facilitate a variety of topological phases, including Chern insulator and quantum spin Hall phases. This distinction arises from the way each fermion…