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Related papers: Free fermions under adaptive quantum dynamics

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Monitored quantum circuits in which entangling unitary dynamics compete with projective local measurements can host measurement-induced phase transitions witnessed by entanglement measures at late times. Adding feedback conditioned on the…

Quantum Physics · Physics 2025-04-17 Haining Pan , Thomas Iadecola , E. M. Stoudenmire , J. H. Pixley

Continuous monitoring of one-dimensional free fermionic systems can generate phenomena reminiscent of quantum criticality, such as logarithmic entanglement growth, algebraic correlations, and emergent conformal invariance, but in a…

Quantum Physics · Physics 2026-05-12 Clemens Niederegger , Tatiana Vovk , Elias Starchl , Lukas M. Sieberer

Monitored quantum systems undergo Measurement-induced Phase Transitions (MiPTs) stemming from the interplay between measurements and unitary dynamics. When the detector readout is post-selected to match a given value, the dynamics is…

Quantum Physics · Physics 2023-12-22 Chun Y. Leung , Dganit Meidan , Alessandro Romito

We study the entanglement dynamics in a generic quantum automaton circuit subjected to projective measurements. We design an efficient algorithm which not only allows us to perform large scale simulation for the R\'enyi entropy but also…

Quantum Physics · Physics 2021-01-07 Jason Iaconis , Andrew Lucas , Xiao Chen

We consider monitored quantum systems with a global conserved charge, and ask how efficiently an observer ("eavesdropper") can learn the global charge of such systems from local projective measurements. We find phase transitions as a…

We address entanglement transitions in monitored random quantum circuits of non-interacting fermions, in particular, the question of whether Born-rule and forced measurements yield the same universality class. For a generic circuit with no…

Statistical Mechanics · Physics 2023-02-21 Chao-Ming Jian , Hassan Shapourian , Bela Bauer , Andreas W. W. Ludwig

We investigate entanglement dynamics in continuously monitored open quantum systems featuring current-carrying non-equilibrium states. We focus on a prototypical one-dimensional model of boundary-driven non-interacting fermions with…

Statistical Mechanics · Physics 2022-07-12 Xhek Turkeshi , Lorenzo Piroli , Marco Schirò

Dynamical quantum systems both driven by unitary evolutions and monitored through measurements have proved to be fertile ground for exploring new dynamical quantum matters. While the entanglement structure and symmetry properties of…

Quantum Physics · Physics 2025-11-10 Haining Pan , Hassan Shapourian , Chao-Ming Jian

Universal features of chaotic quantum dynamics underlie our understanding of thermalization in closed quantum systems and the complexity of quantum computations. Reversible automaton circuits, comprised of classical logic gates, have…

Quantum Physics · Physics 2026-03-11 Ben T. McDonough , Claudio Chamon , Justin H. Wilson , Thomas Iadecola

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

Adaptive quantum circuits-where a quantum many-body state is controlled using measurements and conditional unitary operations-are a powerful paradigm for state preparation and quantum error correction tasks. They can support two types of…

Quantum Physics · Physics 2025-06-30 Thomas Iadecola , Justin H. Wilson , J. H. Pixley

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 explore the dynamical phases of unitary Clifford circuits with variable-range interactions, coupled to a monitoring environment. We investigate two classes of models, distinguished by the action of the unitary gates, which either are…

Quantum Physics · Physics 2022-06-08 Shraddha Sharma , Xhek Turkeshi , Rosario Fazio , Marcello Dalmonte

In recent years, measurement induced entanglement transitions (MIETs) have attracted significant attention. However, the dynamical transition associated with the feedback induced skin effect, which exhibits a wealth of intriguing phenomena,…

Quantum Physics · Physics 2025-05-30 Xuyang Huang , Han-Ze Li , Yu-Jun Zhao , Shuo Liu , Jian-Xin Zhong

In this paper we analyze the ground state phase diagram of a class of fermionic Hamiltonians by looking at the fidelity of ground states corresponding to slightly different Hamiltonian parameters. The Hamiltonians under investigation can be…

Quantum Physics · Physics 2009-11-13 M. Cozzini , P. Giorda , P. Zanardi

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

Symmetry is a powerful tool for understanding phases of matter in equilibrium. Quantum circuits with measurements have recently emerged as a platform for novel states of matter intrinsically out of equilibrium. Can symmetry be used as an…

Quantum Physics · Physics 2025-06-18 Zhi Li , Zhu-Xi Luo

Repeated projective measurements in unitary circuits can lead to an entanglement phase transition as the measurement rate is tuned. In this work, we consider a different setting in which the projective measurements are replaced by…

Quantum Physics · Physics 2024-01-25 Raúl Morral-Yepes , Adam Smith , S. L. Sondhi , Frank Pollmann

We study measurement-induced entanglement and control phase transitions in a quantum analog of the Bernoulli map subjected to a classically-inspired control protocol. When entangling gates are restricted to the Clifford group, separate…

Disordered Systems and Neural Networks · Physics 2023-09-12 Conner LeMaire , Andrew A. Allocca , J. H. Pixley , Thomas Iadecola , Justin H. Wilson