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Related papers: Spacing ratios in mixed-type systems

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Motivated by the role that spectral properties play for the dynamical evolution of a quantum many-body system, we investigate the level spacing statistic of the extended Bose-Hubbard model. In particular, we focus on the distribution of the…

Quantum Gases · Physics 2010-08-18 Corinna Kollath , Guillaume Roux , Giulio Biroli , Andreas Laeuchli

We obtain analytic formulae for the spacing between conductance peaks in the Coulomb blockade regime, based on the universal Hamiltonian model of quantum dots. New random matrix theory results are developed in order to treat correlations…

Mesoscale and Nanoscale Physics · Physics 2008-02-04 D. Herman , T. T. Ong , Gonzalo Usaj , H. Mathur , H. U. Baranger

Quantum many-body systems are commonly considered as quantum chaotic if their spectral statistics, such as the level spacing distribution, agree with those of random matrix theory. Using the example of the kicked Ising chain we demonstrate…

Quantum Physics · Physics 2023-10-16 Tabea Herrmann , Maximilian F. I. Kieler , Arnd Bäcker

We consider the frequency at which avoided crossings appear in an energy level structure when an external field is applied to a quantum chaotic system. The distribution of the spacing in the parameter between two adjacent avoided crossings…

Chaotic Dynamics · Physics 2009-11-11 Manabu Machida , Keiji Saito

Spectral statistics of quantum systems have been studied in detail using the nearest neighbour level spacings, which for generic chaotic systems follows random matrix theory predictions. In this work, the probability density of the closest…

Chaotic Dynamics · Physics 2019-01-23 Shashi C. L. Srivastava , Arul Lakshminarayan , Steven Tomsovic , Arnd Bäcker

We apply Tsallis's q-indexed nonextensive entropy to formulate a random matrix theory (RMT), which may be suitable for systems with mixed regular-chaotic dynamics. We consider the super-extensive regime of q < 1. We obtain analytical…

Mathematical Physics · Physics 2011-12-06 A. Abd El-Hady , A. Y. Abul-Magd

The statistical properties of spectra of quantum systems within the framework of random matrix theory is widely used in many areas of physics. These properties are affected, if two or more sets of spectra are superposed, resulting from the…

Statistical Mechanics · Physics 2021-08-16 Udaysinh T. Bhosale

The energy level statistics of 2D electrons with spin-orbit scattering are considered near the disorder induced metal-insulator transition. Using the Ando model, the nearest-level-spacing distribution is calculated numerically at the…

Condensed Matter · Physics 2009-10-28 L. Schweitzer , I. Kh. Zharekeshev

In the framework of a random matrix description of chaotic quantum scattering the positions of $S-$matrix poles are given by complex eigenvalues $Z_i$ of an effective non-Hermitian random-matrix Hamiltonian. We put forward a conjecture on…

Condensed Matter · Physics 2009-10-31 Yan V. Fyodorov , Mikhail Titov , H. -J. Sommers

We derive the explicit expression for the distribution of resonance widths in a chaotic quantum system coupled to continua via M equivalent open channels. It describes a crossover from the $\chi^2$ distribution (regime of isolated…

Condensed Matter · Physics 2009-10-28 Yan V. Fyodorov , H. -J. Sommers

We review the ideas of how random matrix theory has to be properly applied to quantum physics; particularly we focus on how the spectrum has to be properly prepared and the random matrix correctly identified before the random matrix and the…

Quantum Physics · Physics 2026-04-28 Mario Kieburg

Level-spacing distributions of the Gaussian Unitary Ensemble (GUE) of random matrix theory are expressed in terms of solutions of coupled differential equations. Series solutions up to order 50 in the level spacing are obtained, thus…

Disordered Systems and Neural Networks · Physics 2007-05-23 Uwe Grimm

Random Matrix Theory (RMT) is capable of making predictions for the spectral fluctuations of a physical system only after removing the influence of the level density by unfolding the spectra. When the level density is known, unfolding is…

Statistical Mechanics · Physics 2013-12-16 Ashraf A. Abul-Magd , Adel Y. Abul-Magd

We derive a trace formula that expresses the level density of chaotic many-body systems as a smooth term plus a sum over contributions associated to solutions of the nonlinear Schr\"odinger (or Gross-Pitaevski) equation. Our formula applies…

Chaotic Dynamics · Physics 2016-03-07 Rémy Dubertrand , Sebastian Müller

Random band matrices relevant for open chaotic systems are introduced and studied. The scattering model based on such matrices may serve for the description of preequilibrium chaotic scattering. In the limit of a large number of open…

chao-dyn · Physics 2008-02-03 D. V. Savin

We compute the joint distribution of two consecutive eigenphase spacings and their ratio for Haar-distributed $\mathrm{U}(N)$ matrices (the circular unitary ensemble) using our framework for J\'{a}nossy densities in random matrix theory,…

Mathematical Physics · Physics 2025-07-29 Shinsuke M. Nishigaki

Arising as a fluctuation phenomenon, the equilibrium distribution of meandering steps with mean separation $<\ell>$ on a "tilted" surface can be fruitfully analyzed using results from RMT. The set of step configurations in 2D can be mapped…

Statistical Mechanics · Physics 2009-11-10 T. L. Einstein

We introduce the notion of multi-dimensional chaos that applies to processes described by erratic functions of several dynamical variables. We employ this concept in the interpretation of classical and quantum scattering off a pinball…

High Energy Physics - Theory · Physics 2026-05-27 Massimo Bianchi , Maurizio Firrotta , Jacob Sonnenschein , Dorin Weissman

The typicality approach and the Hilbert space averaging method as its technical manifestation are important concepts of quantum statistical mechanics. Extensively used for expectation values we extend them in this paper to transition…

Quantum Physics · Physics 2020-08-25 Nico Hahn , Thomas Guhr , Daniel Waltner

We propose a generalization of the random matrix theory following the basic prescription of the recently suggested concept of superstatistics. Spectral characteristics of systems with mixed regular-chaotic dynamics are expressed as weighted…

Statistical Mechanics · Physics 2007-05-23 A. Y. Abul-Magd