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arXiv · 2112.09787

Topological transitions with continuously monitored free fermions

Graham Kells·Dganit Meidan·Alessandro Romito
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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.

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Graham Kells, Dganit Meidan, Alessandro Romito. 2021-12-17. Topological transitions with continuously monitored free fermions. https://doi.org/10.21468/scipostphys.14.3.031

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