Symmetry-resolved entanglement and negativity in systems with U(1) symmetry
Sara Murciano (International School for Advanced Studies)
Onsite seminar + zoom (ID: 948 1788 3604, Passcode: B3McPy).
Symmetries are a pillar of modern physics and an evergreen research topic is the characterisation of how the presence of a symmetry influences the properties of a physical system. I will present an analysis of the entanglement entropies and negativities related to different symmetry sectors of systems with an internal U(1) symmetry. The entanglement entropy admits a decomposition according to its total preserved charge thanks to the block diagonal form of the density matrix. Despite this structure becomes nontrivial after the operation of partial transposition on the density matrix, it has been shown that negativity admits a resolution in terms of the charge imbalance between two subsystems. I will focus on the resolution of entanglement and negativity for free Dirac fields in two spacetime dimensions at finite temperature and size. To this end, I use a geometrical construction in terms of an Aharonov-Bohm-like flux inserted in the Riemann surface defining the entanglement. The main interesting finding is that both entanglement entropy and negativity are equally distributed among the different symmetry sectors at leading order.