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Related papers: Disordered monitored free fermions

200 papers

We study the time evolution after a quantum quench in a family of models whose degrees of freedom are fermions coupled to spins, where quenched disorder appears neither in the Hamiltonian parameters nor in the initial state. Focussing on…

Strongly Correlated Electrons · Physics 2017-10-27 Adam Smith , Johannes Knolle , Roderich Moessner , Dmitry L. Kovrizhin

We introduce a class of hybrid quantum circuits, with random unitaries and projective measurements, which host long-range order in the area law entanglement phase of the steady state. Our primary example is circuits with unitaries…

Statistical Mechanics · Physics 2021-06-22 Shengqi Sang , Timothy H. Hsieh

Monitored quantum circuits (MRCs) exhibit a measurement-induced phase transition between area-law and volume-law entanglement scaling. MRCs with a conserved charge additionally exhibit two distinct volume-law entangled phases that cannot be…

We study theoretically and numerically the entanglement entropy of the $d$-dimensional free fermions whose one body Hamiltonian is the Anderson model. Using basic facts of the exponential Anderson localization, we show first that the…

Quantum Physics · Physics 2014-10-15 L. Pastur , V. Slavin

Entanglement measures have emerged as one of the versatile probes to diagnose quantum phases and their transitions. Universal features in them expand their applicability to a range of systems, including those with quenched disorder. In this…

Disordered Systems and Neural Networks · Physics 2024-07-18 Subrata Pachhal , Adhip Agarwala

We numerically investigate measurement-induced phase transitions in monitored free fermions through the spectral and eigenstate properties of the entanglement Hamiltonian. By analyzing entanglement scaling, we identify three non-trivial…

Quantum Physics · Physics 2025-09-11 Karim Chahine , Michael Buchhold

We investigate the dynamics of two-dimensional quantum spin systems under the combined effect of random unitary gates and local projective measurements. When considering steady states, a measurement-induced transition occurs between two…

Statistical Mechanics · Physics 2020-10-16 Xhek Turkeshi , Rosario Fazio , Marcello Dalmonte

The development and spread of entanglement in complex quantum systems is central to exploring many-body phenomena out of equilibrium. Measuring entanglement dynamics can shed light on information scrambling and thermalisation, namely on…

Monitored quantum dynamics reveal quantum state trajectories which exhibit a rich phenomenology of entanglement structures, including a transition from a weakly-monitored volume law entangled phase to a strongly-monitored area law phase.…

Statistical Mechanics · Physics 2023-03-28 Yaodong Li , Sagar Vijay , Matthew P. A. Fisher

The phenomenon of localization usually happens due to the existence of disorder in a medium. Nevertheless, certain quantum systems allow dynamical localization solely due to the nature of internal interactions. We study a discrete time…

Quantum Physics · Physics 2021-02-24 B. Danacı , İ. Yalçınkaya , B. Çakmak , G. Karpat , S. P. Kelly , A. L. Subaşı

Competition among repetitive measurements of noncommuting observables and unitary dynamics can give rise to a wide variety of entanglement phases. Here, we propose a general framework based on Lyapunov analysis to characterize topological…

Quantum Physics · Physics 2025-06-24 Hisanori Oshima , Ken Mochizuki , Ryusuke Hamazaki , Yohei Fuji

A wave function exposed to measurements undergoes pure state dynamics, with deterministic unitary and probabilistic measurement induced state updates, defining a quantum trajectory. For many-particle systems, the competition of these…

Statistical Mechanics · Physics 2021-11-02 M. Buchhold , Y. Minoguchi , A. Altland , S. Diehl

We extend the concept of Anderson localization, the confinement of quantum information in a spatially irregular potential, to quantum circuits. Considering matchgate circuits, generated by time-dependent spin-1/2 XY Hamiltonians, we give an…

Quantum Physics · Physics 2018-07-18 Adrian Chapman , Akimasa Miyake

The Anderson model for independent electrons in a disordered potential is transformed analytically and exactly to a basis of random extended states leading to a variant of augmented space. In addition to the widely-accepted phase diagrams…

Strongly Correlated Electrons · Physics 2007-05-23 Nigel Goldenfeld , Roger Haydock

Waves fail to propagate in random media. First predicted for quantum particles in the presence of a disordered potential, Anderson localization has been observed also in classical acoustics, electromagnetism and optics. Here, for the first…

Disorder-free localization (DFL) is a phenomenon as striking as it appears to be simple: a translationally invariant state evolving under a disorder-free Hamiltonian failing to thermalize. It is predicted to occur in a number of quantum…

Measurement-induced entanglement phase transitions (MIET) highlight how local measurements drive quantum systems between area-law and volume-law entangled states. This review surveys MIET in free fermion models, focusing on how unitary…

Quantum Physics · Physics 2025-07-10 Han-Ze Li , Jian-Xin Zhong , Xue-Jia Yu

Characterizing the delocalization transition in closed quantum systems with a many-body localized phase is a key open question in the field of nonequilibrium physics. We exploit that localization of particles as realized in Anderson and…

Disordered Systems and Neural Networks · Physics 2021-12-17 Miroslav Hopjan , Giuliano Orso , Fabian Heidrich-Meisner

We uncover a dynamical entanglement transition in a monitored quantum system that is heralded by a local order parameter. Classically, chaotic systems can be stochastically controlled onto unstable periodic orbits and exhibit controlled and…

Disordered Systems and Neural Networks · Physics 2022-08-10 Thomas Iadecola , Sriram Ganeshan , J. H. Pixley , Justin H. Wilson

We study one-dimensional spinless fermions with random interactions, but without any on-site disorder. We find that random interactions generically stabilize a many-body localized phase, in spite of the completely extended single-particle…

Statistical Mechanics · Physics 2017-02-01 Xiaopeng Li , Dong-Ling Deng , Yang-Le Wu , S. Das Sarma