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Related papers: Exceptional spectrum and dynamic magnetization

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We study the dynamics of two strongly-interacting fermions moving in 2D lattices under the action of a periodic electric field, both with and without a magnetic flux. Due to the interaction, these particles bind together forming a doublon.…

Quantum Gases · Physics 2019-11-22 Miguel Bello , Charles E. Creffield , Gloria Platero

We consider non-Hermitian dynamics of a quantum particle hopping on a one-dimensional tight-binding lattice made of $N$ sites with asymmetric hopping rates induced by a time-periodic oscillating imaginary gauge field. A deeply different…

Quantum Physics · Physics 2016-08-10 Stefano Longhi

New insights into the microscopic origin of itinerant ferromagnetism were recently gained from investigations of electronic lattice models within dynamical mean-field theory (DMFT). In particular, it is now established that even in the…

Strongly Correlated Electrons · Physics 2007-05-23 D. Vollhardt , N. Blümer , K. Held , M. Kollar

We observe a thermally induced spontaneous magnetization reversal of epitaxial ferromagnet/antiferromagnet heterostructures under a constant applied magnetic field. Unlike any other magnetic system, the magnetization spontaneously reverses,…

Materials Science · Physics 2009-11-11 Zhi-Pan Li , Johannes Eisenmenger , Casey W. Miller , Ivan K. Schuller

We study strongly interacting ultracold spin-1/2 fermions in a honeycomb lattice in the presence of a harmonic trap. Tuning the strength of the harmonic trap we show that it is possible to confine the fermions in artificial structures…

Strongly Correlated Electrons · Physics 2020-03-25 Karla Baumann , Angelo Valli , Adriano Amaricci , Massimo Capone

The spectral, dynamical and topological properties of physical systems described by non-Hermitian (including $\mathcal{PT}$-symmetric) Hamiltonians are deeply modified by the appearance of exceptional points and spectral singularities. Here…

Quantum Physics · Physics 2015-06-18 S. Longhi , G. Della Valle

We study pairwise quantum entanglement in systems of fermions itinerant in a lattice from a second-quantized perspective. Entanglement in the grand-canonical ensemble is studied, both for energy eigenstates and for the thermal state.…

Quantum Physics · Physics 2009-11-07 Paolo Zanardi , Xiaoguang Wang

We analyze a two-dimensional Kondo lattice model with special emphasis on non-Hermitian properties of the single-particle spectrum, following a recent proposal by Kozii and Fu. Our analysis based on the dynamical mean-field theory…

Strongly Correlated Electrons · Physics 2018-08-01 Tsuneya Yoshida , Robert Peters , Norio Kawakami

Weak ergodicity breaking in interacting quantum systems may occur due to the existence of a subspace dynamically decoupled from the rest of the Hilbert space. In two-orbital spinful lattice systems, we construct such subspaces that are in…

Strongly Correlated Electrons · Physics 2026-03-04 Kiryl Pakrouski , K. V. Samokhin

The experimental realization of time dependent ultracold lattice systems has paved the way towards the implementation of new Hubbard-like Hamiltonians. We show that in a one dimensional two components lattice dipolar Fermi gas the…

Quantum Gases · Physics 2017-12-08 S. Fazzini , A. Montorsi , M. Roncaglia , L. Barbiero

Highly accurate numerical results for single-particle spectrum and order parameter are obtained for the magnetically ordered Kondo lattice by means of the dynamical mean-field theory combined with the continuous-time quantum Monte Carlo…

Strongly Correlated Electrons · Physics 2011-02-28 Shintaro Hoshino , Junya Otsuki , Yoshio Kuramoto

Quasiperiodic mosaic systems with the quasiperiodic potential being added periodically with a fixed lattice interval have attracted significant attention due to their peculiar spectral properties with exactly known mobility edges, which…

Disordered Systems and Neural Networks · Physics 2025-01-08 Yu Zhang , Chenguang Liang , Shu Chen

We have analyzed the quantum interference effects in the macroscopic ''superconducting molecule''. The composite system consists of two massive superconducting rings, each interrupted by a Josephson junction, which are at the same time…

Superconductivity · Physics 2009-10-31 R. de Bruyn Ouboter , A. N. Omelyanchouk , E. D. Vol

We study itinerant ferromagnetism in multi-orbital Hubbard models in certain two-dimensional square and three-dimensional cubic lattices. In the strong coupling limit where doubly occupied orbitals are not allowed, we prove that the fully…

Strongly Correlated Electrons · Physics 2014-05-29 Yi Li , Elliott H. Lieb , Congjun Wu

Strongly out-of-equilibrium regimes in magnetic nanostructures exhibit novel properties, linked to the nonlinear nature of magnetization dynamics, which are of great fundamental and practical interest. Here, we demonstrate that field-driven…

An exceptional point is a special point in parameter space at which two (or more) eigenvalues and eigenvectors coincide. The discovery of exceptional points within mechanical and optical systems has uncovered peculiar effects in their…

Quantum Physics · Physics 2025-04-24 C. A. Downing , V. A. Saroka

The collective response of a system is profoundly shaped by the interaction dynamics between its constituent elements. In physics, tailoring these interactions can enable the observation of unusual phenomena that are otherwise inaccessible…

Exceptional points are singularities in the spectrum of non-Hermitian systems in which several eigenvectors are linearly dependent and their eigenvalues are equal to each other. Usually it is assumed that the order of the exceptional point…

Quantum Physics · Physics 2025-12-11 Timofey T. Sergeev , Evgeny S. Andrianov , Alexander A. Zyablovsky

Non-Hermitian Hamiltonians can give rise to exceptional points (EPs) which have been extensively explored with nominally identical coupled resonators. Here a non-Hermitian electromechanical system is developed which hosts vibration modes…

Mesoscale and Nanoscale Physics · Physics 2019-02-06 P. Renault , H. Yamaguchi , I. Mahboob

Non-Hermitian systems with parity-time ($\mathcal{PT}$) symmetry give rise to exceptional points (EPs) with exceptional properties that arise due to the coalescence of eigenvectors. Such systems have been extensively explored in the…