Topological transitions in weakly monitored free fermions

Monday, March 13, 2023 - 00:00



Graham Kells, Dganit Meidan, Alessandro Romito

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.

SciPost Phys. 14, 031 (2023) · published 13 March 2023

Cited by 2: 

Kawabata et al., Entanglement Phase Transition Induced by the Non-Hermitian Skin Effect
Phys. Rev. X 13, 021007 (2023) [Crossref]

Feng et al., Absence of logarithmic and algebraic scaling entanglement phases due to the skin effect
Phys. Rev. B 107, 094309 (2023) [Crossref]