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Related papers: Quantum criticality of hot random spin chains

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We extend the recently introduced strong disorder renormalization group method in real space, well suited to study bond disordered antiferromagnetic power law coupled quantum spin chains, to study excited states, and finite temperature…

Disordered Systems and Neural Networks · Physics 2026-04-23 Stefan Kettemann

Recently has been observed for some one-dimensional models that exhibit unexpected pseudo-transitions and quasi-phases. This pseudo-transition resembles a first- and second-order phase transition simultaneously. One of those models is the…

Strongly Correlated Electrons · Physics 2018-06-18 I. M. Carvalho , J. Torrico , S. M. de Souza , M. Rojas , O. Rojas

We investigate the ground-state and the finite-temperature properties of the bond-random $s=1/2$ Heisenberg model on a square lattice with frustrating nearest- and next-nearest-neighbor antiferromagnetic interactions, $J_1$ and $J_2$, by…

Strongly Correlated Electrons · Physics 2018-10-26 Kazuki Uematsu , Hikaru Kawamura

Nonintegrable many-body quantum systems typically thermalize at long times through the mechanism of quantum chaos. However, some exceptional systems, such as those harboring quantum scars, break thermalization, serving as testbeds for…

We analyze quantum criticality at finite temperature for a class of non-Fermi liquids with massless bosons. Finite temperature gives rise to new infrared singularities that invalidate standard perturbative treatments. We show how such…

Strongly Correlated Electrons · Physics 2017-10-25 Huajia Wang , Gonzalo Torroba

The magnetic insulator copper pyrazine dinitrate comprises antiferromagnetic spin-1/2 chains that are well described by the exactly solvable one-dimensional Heisenberg model, providing a unique opportunity for a quantitative comparison…

Strongly Correlated Electrons · Physics 2018-01-04 Oliver Breunig , Markus Garst , Andreas Klümper , Jens Rohrkamp , Mark M. Turnbull , Thomas Lorenz

Studies of disordered spin chains have recently experienced a renewed interest, inspired by the question to which extent the exact numerical calculations comply with the existence of a many-body localization phase transition. For the…

Disordered Systems and Neural Networks · Physics 2022-01-05 Lev Vidmar , Bartosz Krajewski , Janez Bonca , Marcin Mierzejewski

We study a quantum spin-1/2 chain that is dual to the canonical problem of non-equilibrium Kawasaki dynamics of a classical Ising chain coupled to a thermal bath. The Hamiltonian is obtained for the general disordered case with non-uniform…

Statistical Mechanics · Physics 2022-03-29 Stéphane Vinet , Gabriel Longpré , William Witczak-Krempa

At quantum critical points (QCP) \cite{Pfeuty:1971,Young:1975,Hertz:1976,Chakravarty:1989,Millis:1993,Chubukov:1 994,Coleman:2005} there are quantum fluctuations on all length scales, from microscopic to macroscopic lengths, which,…

Strongly Correlated Electrons · Physics 2007-05-23 Angela Kopp , Sudip Chakravarty

Quantum and global discord in a spin-1 Heisenberg chain subject to single-ion anisotropy (uniaxial field) are studied using exact diagonalisation and the density matrix renormalisation group (DMRG). We find that these measures of quantum…

Quantum Physics · Physics 2015-06-09 Matthew J. M. Power , Steve Campbell , Maria Moreno-Cardoner , Gabriele De Chiara

We use exact diagonalization to explore the many-body localization transition in a random-field spin-1/2 chain. We examine the correlations within each many-body eigenstate, looking at all high-energy states and thus effectively working at…

Disordered Systems and Neural Networks · Physics 2015-05-20 Arijeet Pal , David A. Huse

We show that the effective action of the quantum spherical spin glass is invariant under a generalized form of the Becchi-Rouet-Stora-Tyutin(BRST) supersymmetry. The Ward identities associated to this invariance indicate that the spin glass…

Disordered Systems and Neural Networks · Physics 2007-05-23 Pedro Castro Menezes , Alba Theumann

The entangling power of a unitary operator quantifies its ability to generate entanglement from product states and provides a natural probe of quantum many-body dynamics. Entanglement extremization at points of enhanced symmetry has…

Quantum Physics · Physics 2026-05-21 Ian Low , Pallab Goswami

It is often expected (and assumed) for a quantum chaotic system that the presence of correlated eigenvalues implies that all the other properties as dictated by random matrix theory are satisfied. We demonstrate using the spin-$1/2$ kicked…

Quantum Physics · Physics 2025-05-23 Tanay Pathak , Masaki Tezuka

We investigate the specific heat, $c$, near an Ising nematic quantum critical point (QCP), using sign problem-free quantum Monte Carlo simulations. Cooling towards the QCP, we find a broad regime of temperature where $c/T$ is close to the…

Strongly Correlated Electrons · Physics 2021-07-16 Ori Grossman , Johannes S. Hofmann , Tobias Holder , Erez Berg

Quantum criticality is a fundamental organizing principle for studying strongly correlated systems. Nevertheless, understanding quantum critical dynamics at nonzero temperatures is a major challenge of condensed matter physics due to the…

Strongly Correlated Electrons · Physics 2018-06-19 Jianda Wu , Wang Yang , Congjun Wu , Qimiao Si

We find energy-dependent hysteresis in an isolated Heisenberg quantum spin system, similar to thermomagnetic hysteresis in canonical spin glasses in contact with a thermal reservoir. Analogous to zero-field cooling and field cooling in…

We investigate the two-dimensional frustrated quantum Heisenberg model with bond disorder on nearest-neighbor couplings using the recently introduced Foundation Neural-Network Quantum States framework, which enables accurate and efficient…

We reinvestigate the behavior of the conductivity of several disordered quantum lattice models at infinite temperature using exact diagonalization. Contrary to the conclusion drawn in a recent investigation of similar quantities in…

Disordered Systems and Neural Networks · Physics 2013-05-29 Timothy C. Berkelbach , David R. Reichman

We study the critical behavior of two-dimensional short-range quantum spin glasses by numerical simulations. Using a parallel tempering algorithm, we calculate the Binder cumulant for the Ising spin glass in a transverse magnetic field with…

Statistical Mechanics · Physics 2016-07-26 D. A. Matoz-Fernandez , F. Roma