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Related papers: A bandmixing treatment for multiband-coupled syste…

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In a multiband Hubbard model the self-consistency relations for the two-body bound-state bands are in the form of a nonlinear eigenvalue problem. Assuming that the resultant eigenvectors form an orthonormal set, e.g., in the strong-binding…

Quantum Gases · Physics 2023-06-02 M. Iskin

The paper studies inverse problems of determining unknown coefficients in various semi-linear and quasi-linear wave equations. We introduce a method to solve inverse problems for non-linear equations using interaction of three waves, that…

Analysis of PDEs · Mathematics 2023-05-10 Ali Feizmohammadi , Matti Lassas , Lauri Oksanen

Non-Hermiticity naturally breaks down the adiabaticity and thus leads to non-Abelian behaviors in multi-band systems. Here, we study how non-Abelian properties emerge in non-Hermitian systems by considering a multi-band non-Hermitian model…

Mesoscale and Nanoscale Physics · Physics 2025-09-17 Ziyu Zhou , Zhi-Cong Xu , Li-Jun Lang

The differential equations governing the late-time ring-down of the perturbations of the Kerr metric, the Teukolsky Angular Equation and the Teukolsky Radial Equation, can be solved analytically in terms of confluent Heun functions. In this…

High Energy Astrophysical Phenomena · Physics 2012-12-24 Denitsa Staicova , Plamen Fiziev

Waveguide Quantum Electrodynamics (WQED) offers a suitable stage for controlling the interaction of light with atoms, allowing for collective phenomena such as super- and subradiance. In a chiral waveguide setup, the quantum state evolves…

Quantum Physics · Physics 2026-03-06 M. Eltohfa , F. Robicheaux

We discuss the decay rates of chaotic quantum systems coupled to noise. We model both the Hamiltonian and the system-noise coupling by random $N \times N$ Hermitian matrices, and study the spectral properties of the resulting Lindblad…

Quantum Physics · Physics 2019-12-11 Tankut Can , Vadim Oganesyan , Dror Orgad , Sarang Gopalakrishnan

The limit distribution of the discrete spectrum of the Sturm-Liouville problem with complex-valued polynomial potential on an interval, on a half-axis, and on the entire axis is studied. It is shown that at large parameter values, the…

Spectral Theory · Mathematics 2016-04-20 A. A. Shkalikov , S. N. Tumanov

This paper describes a novel numerical approach to find the statistics of the non-stationary response of scalar non-linear systems excited by L\'evy white noises. The proposed numerical procedure relies on the introduction of an integral…

Statistical Mechanics · Physics 2011-08-09 Giulio Cottone

We introduce a computationally efficient method to calculate the quasiparticle (QP) band structure of general van der Waals (vdW) heterostructures. A layer-projected scissors (LAPS) operator, which depends on the one-body density matrix, is…

This paper is concerned with the asymptotic description of high-frequency waves in locally periodic media. A key issue is that the Bloch-dispersion curves vary with the local microstructure, giving rise to hidden singularities associated…

Optics · Physics 2016-12-13 Ory Schnitzer

In this study, we investigate the pseudospectrum and spectrum (in)stability of quantum corrected Schwarzschild black hole. Methodologically, we use the hyperboloidal framework to cast the quasinormal mode (QNM) problem into an eigenvalue…

General Relativity and Quantum Cosmology · Physics 2024-06-14 Li-Ming Cao , Jia-Ning Chen , Liang-Bi Wu , Libo Xie , Yu-Sen Zhou

Non-Hermitian operators are now routinely used to describe few-mode systems such as optical resonators and superconducting qubits, and exceptional points (EPs) are defective spectral singularities of such non-Hermitian operators. In…

Quantum Physics · Physics 2026-05-27 Okuto Morikawa , Shoya Ogawa , Soma Onoda

We make use of the Quantum Hamilton-Jacobi (QHJ) theory to investigate conditional quasi-solvability of the quantum symmetric top subject to combined electric fields (symmetric top pendulum). We derive the conditions of quasi-solvability of…

Mathematical Physics · Physics 2023-02-09 Konrad Schatz , Bretislav Friedrich , Simon Becker , Burkhard Schmidt

This paper addresses the problem of computing the eigenvalues lying in the gaps of the essential spectrum of a periodic Schrodinger operator perturbed by a fast decreasing potential. We use a recently developed technique, the so called…

Spectral Theory · Mathematics 2009-11-13 Lyonell Boulton , Michael Levitin

Hyperspectral unmixing is one of the crucial steps for many hyperspectral applications. The problem of hyperspectral unmixing has proven to be a difficult task in unsupervised work settings where the endmembers and abundances are both…

Computer Vision and Pattern Recognition · Computer Science 2013-06-03 Ying Wang , Chunhong Pan , Shiming Xiang , Feiyun Zhu

Bound states of hyperbolic potential is investigated by means of a generalized pseudospectral method. Significantly improved eigenvalues, eigenfunctions are obtained efficiently for arbitrary $n, \ell$ quantum states by solving the relevant…

Chemical Physics · Physics 2015-06-22 Amlan K. Roy

The multipartite non-Hermitian Su-Schrieffer-Heeger model is explored as a prototypical example of one-dimensional systems with several sublattice sites for unveiling intriguing insulating and metallic phases with no Hermitian counterparts.…

Mesoscale and Nanoscale Physics · Physics 2022-05-10 Ritu Nehra , Dibyendu Roy

In this second paper, we develop transferable semi-empirical parameters for the technologically important material, silicon, using Extended Huckel Theory (EHT) to calculate its electronic structure. The EHT-parameters areoptimized to…

Materials Science · Physics 2009-11-11 Diego Kienle , Jorge I. Cerda , Kirk H. Bevan , Gengchiau Liang , Lutfe Siddiqui , Avik W. Ghosh

The mixed states are important in quantum optics since they frequently appear in the decoherence problems. When one of the components of the system is prepared in the mixed state and the evolution operator of this system is not available,…

Quantum Physics · Physics 2011-02-24 Faisal A. A. El-Orany

A pseudospectrum analysis has recently provided evidence of a potential generic instability of black hole (BH) quasinormal mode (QNM) overtones under high-frequency perturbations. Such instability analysis depends on the assessment of the…

General Relativity and Quantum Cosmology · Physics 2022-06-08 Edgar Gasperin , José Luis Jaramillo