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Related papers: Krylov complexity in saddle-dominated scrambling

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In this work we probe the operator growth for systems with Lie symmetry using tools from quantum information. Namely, we investigate the Krylov complexity, entanglement negativity, von Neumann entropy and capacity of entanglement for…

High Energy Physics - Theory · Physics 2022-06-15 Dimitrios Patramanis

Exponential growth in the out-of-time-order correlator (OTOC) is an important potential signature of quantum chaos. The OTOC is quite simple to calculate for squeezed states, whose applications are frequently found in quantum optics and…

High Energy Physics - Theory · Physics 2021-02-03 S. Shajidul Haque , Bret Underwood

We introduce and review a new complexity measure, called `Krylov complexity', which takes its origins in the field of quantum-chaotic dynamics, serving as a canonical measure of operator growth and spreading. Krylov complexity, underpinned…

High Energy Physics - Theory · Physics 2025-07-10 Eliezer Rabinovici , Adrián Sánchez-Garrido , Ruth Shir , Julian Sonner

We study the operator growth in open quantum systems with dephasing dissipation terms, extending the Krylov complexity formalism of Phys. Rev. X 9, 041017. Our results are based on the study of the dissipative $q$-body Sachdev-Ye-Kitaev…

Quantum Physics · Physics 2023-03-10 Budhaditya Bhattacharjee , Xiangyu Cao , Pratik Nandy , Tanay Pathak

We study Krylov complexity in Lifshitz-type Dirac field theories with a generic dynamical critical exponent $z$. By computing the Lanczos coefficients for massless and massive cases, we analyze the growth and saturation behavior of Krylov…

High Energy Physics - Theory · Physics 2025-11-11 Hamid R. Imani , Komeil Babaei Velni , M. Reza Mohammadi Mozaffar

Building upon recent research in spin systems with non-local interactions, this study investigates operator growth using the Krylov complexity in different non-local versions of the Ising model. We find that the non-locality results in a…

Quantum Physics · Physics 2025-03-11 Aranya Bhattacharya , Pingal Pratyush Nath , Himanshu Sahu

We use Krylov complexity to study operator growth in the $q$-body dissipative SYK model, where the dissipation is modeled by linear and random $p$-body Lindblad operators. In the large $q$ limit, we analytically establish the linear growth…

Quantum Physics · Physics 2024-01-18 Budhaditya Bhattacharjee , Pratik Nandy , Tanay Pathak

Scrambling is a key concept in the analysis of nonequilibrium properties of quantum many-body systems. Most studies focus on its characterization via out-of-time-ordered correlation functions (OTOCs), particularly through the early-time…

Quantum Physics · Physics 2023-04-14 Sivaprasad Omanakuttan , Karthik Chinni , Philip Daniel Blocher , Pablo M. Poggi

We study Krylov complexity in Schr\"odinger field theory in the grand canonical ensemble with chemical potential $\mu$, with an emphasis on the qualitatively new features that arise for $\mu>0$. In this regime the fermionic Wightman power…

High Energy Physics - Theory · Physics 2026-03-02 Peng-Zhang He , Lei-Hua Liu , Hai-Qing Zhang , Qing-Quan Jiang

The presence of chaos in classical Hamiltonian systems is witnessed by its maximal Lyapunov exponent, that quantifies the instability of motion through the exponential growth of indicators such as the trace of the stability matrix or the…

Chaotic Dynamics · Physics 2026-03-30 Thomas R. Michel , Mathias Steinhuber , Juan Diego Urbina , Peter Schlagheck

Out-of-Time-Order Correlators (OTOCs) quantify quantum information scrambling, but their connection to localized phase-space structures, such as chemical transition states, requires formal development. We derive a leading-order…

Quantum Physics · Physics 2026-04-15 Stephen Wiggins

Krylov complexity has recently emerged as a useful probe of operator growth and quantum dynamics in many-body systems and holographic dualities. In this paper we study its behavior in the Veneziano--Wosiek model, a supersymmetric matrix…

High Energy Physics - Theory · Physics 2026-03-24 Eleonora Alfinito , Matteo Beccaria

Out-of-time-order correlators (OTOCs) have been proposed as sensitive probes for chaos in interacting quantum systems. They exhibit a characteristic classical exponential growth, but saturate beyond the so-called scrambling or Ehrenfest…

Statistical Mechanics · Physics 2018-09-25 Josef Rammensee , Juan-Diego Urbina , Klaus Richter

Scrambling, a process in which quantum information spreads over a complex quantum system becoming inaccessible to simple probes, happens in generic chaotic quantum many-body systems, ranging from spin chains, to metals, even to black holes.…

Quantum Physics · Physics 2020-02-10 Shenglong Xu , Brian Swingle

Recently, Krylov complexity was proposed as a measure of complexity and chaoticity of quantum systems. We consider the stadium billiard as a typical example of the quantum mechanical system obtained by quantizing a classically chaotic…

High Energy Physics - Theory · Physics 2024-01-22 Koji Hashimoto , Keiju Murata , Norihiro Tanahashi , Ryota Watanabe

In this paper, we studied a set of generalised Krylov complexity for operator growth. We demonstrate their universal features at both initial times and long times using half-analytical technique as well as numerical results. In particular,…

High Energy Physics - Theory · Physics 2023-12-12 Zhong-Ying Fan

We study information scrambling, as diagnosed by the out-of-time order correlations (OTOCs), in a system of large spins collectively interacting via spatially inhomogeneous and incommensurate exchange couplings. The model is realisable in a…

Quantum Gases · Physics 2019-05-22 J. Marino , A. M. Rey

Inspired by the universal operator growth hypothesis, we extend the formalism of Krylov construction in dissipative open quantum systems connected to a Markovian bath. Our construction is based upon the modification of the Liouvillian…

Quantum Physics · Physics 2022-12-19 Aranya Bhattacharya , Pratik Nandy , Pingal Pratyush Nath , Himanshu Sahu

Fast scrambling of quantum correlations, reflected by the exponential growth of Out-of-Time-Order Correlators (OTOCs) on short pre-Ehrenfest time scales, is commonly considered as a major quantum signature of unstable dynamics in quantum…

Quantum Physics · Physics 2023-08-22 Mathias Steinhuber , Peter Schlagheck , Juan-Diego Urbina , Klaus Richter

The complexity of quantum evolutions can be understood by examining their dispersion in a chosen basis. Recent research has stressed the fact that the Krylov basis is particularly adept at minimizing this dispersion [V. Balasubramanian et…

Quantum Physics · Physics 2023-09-26 Gastón F. Scialchi , Augusto J. Roncaglia , Diego A. Wisniacki