27 citations · 64 across the 9 of their papers we have counts for
11 papers · 1 filter
Long-range entangled criticality from coherent errors
Amir-Reza Negari, Subhayan Sahu, Jan Behrends +2
We find that coherent error can induce a phase transition from the clean surface code phase into an extended long-range entangled critical regime with diverging Markov length. To d…
Instability of Markov chains under infinitesimal coherent dissipation
Amir-Reza Negari, Yijian Zou, Timothy H. Hsieh
Under local Lindbladian evolution, the growth of conditional mutual information and its associated Markov length scale is not limited by Lieb-Robinson bounds, yet it has been uncle…
Nonadditivity in fermionic quantum Shannon theory
Farzin Salek, Amir-Reza Negari, Graeme Smith +2
We study collective state preparation and channel encoding in fermionic systems under parity superselection and composition governed by the canonical anticommutation relations. For…
Entanglement of purification for Werner states: canonical purification and nonadditivity
Zahra Baghali Khanian, Amir-Reza Negari
We prove that the von Neumann entanglement of purification is nonadditive. For two-qubit Werner states with singlet weight , we show that canonical purifica…
Approximation theorems for fermionic Gaussian states
Amir-Reza Negari, Farzin Salek, Zoltán Zimborás +3
A recurring principle in many-body physics is that sufficiently distributed interactions or correlations lead to an effectively mean-field description. For fermionic Gaussian state…
Rényi Entanglement of Purification Is Non-additive
Amir-Reza Negari, Zahra Baghali Khanian
Entanglement of purification is a fundamental measure of total correlations whose additivity remains unresolved. We study its additivity for classical states on two qubits at diffe…
Critical non-equilibrium phases from noisy topological memories
Amir-Reza Negari, Subhayan Sahu, Jan Behrends +2
We demonstrate the existence of an extended non-equilibrium critical phase, characterized by sub-exponential decay of conditional mutual information (CMI), in the surface code subj…
Symmetry enforces entanglement at high temperatures
Amir-Reza Negari, Leonardo A. Lessa, Subhayan Sahu
Many-body quantum systems with local interactions undergo ``sudden death of entanglement" at high temperatures, whereby thermal states become classical mixtures of product states.…
Extendibility of Fermionic Gaussian States
Amir-Reza Negari, Farzin Salek
We investigate -extendibility of fermionic Gaussian states, a property central to quantum correlations and approximations of separability. We show that these states are…
Spacetime Markov length: a diagnostic for fault tolerance via mixed-state phases
Amir-Reza Negari, Tyler D. Ellison, Timothy H. Hsieh
We establish a correspondence between the fault-tolerance of local stabilizer codes experiencing measurement and physical errors and the mixed-state phases of decohered resource st…
Measurement-induced phase transitions in the toric code
Amir-Reza Negari, Subhayan Sahu, Timothy H. Hsieh
We show how distinct phases of matter can be generated by performing random single-qubit measurements on a subsystem of toric code. Using a parton construction, such measurements m…