English

Topological transitions with continuously monitored free fermions

Quantum Physics 2023-03-15 v3 Mesoscale and Nanoscale Physics Statistical Mechanics

Abstract

We study a free fermion model where two sets of non-commuting non-projective measurements stabilize area-law entanglement scaling phases of distinct topological order. We show the presence of a topological phase transition that is of a different universality class than that observed in stroboscopic projective circuits. In the presence of unitary dynamics, the two topologically distinct phases are separated by a region with sub-volume scaling of the entanglement entropy. We find that this entanglement transition is well identified by a combination of the bipartite entanglement entropy and the topological entanglement entropy. We further show that the phase diagram is qualitatively captured by an analytically tractable non-Hermitian model obtained via post-selecting the measurement outcome. Finally we introduce a partial-post-selection continuous mapping, that uniquely associates topological indices of the non-Hermitian Hamiltonian to the distinct phases of the stochastic measurement-induced dynamics.

Keywords

Cite

@article{arxiv.2112.09787,
  title  = {Topological transitions with continuously monitored free fermions},
  author = {Graham Kells and Dganit Meidan and Alessandro Romito},
  journal= {arXiv preprint arXiv:2112.09787},
  year   = {2023}
}

Comments

19 pages, 9 figures, expanded Sec III, added appendix B

R2 v1 2026-06-24T08:22:42.198Z