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Weakly interacting Fermi gases exhibit rich collective dynamics in spin-dependent potentials, arising from correlations between spin degrees of freedom and conserved single atom energies, offering broad prospects for simulating many-body…

Quantum Gases · Physics 2021-01-28 S. Pegahan , J. Kangara , I. Arakelyan , J. E. Thomas

The normalization of scattering states is more than a rote step necessary to calculate expectation values. This normalization actually contains important information regarding the density of the scattering spectrum (along with useful…

Quantum Physics · Physics 2025-05-27 Chris L. Lin

The propagator of a physical degree of freedom ought to obey a K\"{a}ll\'{e}n-Lehmann spectral representation, with positive spectral density. The latter quantity is directly related to a cross section based on the optical theorem. The…

High Energy Physics - Lattice · Physics 2012-10-30 O. Oliveira , D. Dudal , P. J. Silva

The spectral density of random matrices is studied through a quaternionic generalisation of the Green's function, which precisely describes the mean spectral density of a given matrix under a particular type of random perturbation. Exact…

Mathematical Physics · Physics 2011-04-08 Tim Rogers

Magnetic materials play a key role in the contemporary industry, providing unique features with a wide application potential. To study physical phenomena and design new materials, it is important to possess an appropriate tool, a model…

Materials Science · Physics 2026-01-13 Jakub Šebesta , Dominik Legut

The spectral gap problem - determining whether the energy spectrum of a system has an energy gap above ground state, or if there is a continuous range of low-energy excitations - pervades quantum many-body physics. Recently, this important…

Quantum Physics · Physics 2020-08-19 Johannes Bausch , Toby Cubitt , Angelo Lucia , David Perez-Garcia

A phenomenological approach is presented that allows one to model, and thereby interpret, photoemission spectra of strongly correlated electron systems. A simple analytical formula for the self-energy is proposed. This self-energy describes…

Strongly Correlated Electrons · Physics 2009-11-07 Krzysztof Byczuk , Ralf Bulla , Ralph Claessen , Dieter Vollhardt

The full spectrum of transfer matrices of the general eight-vertex model on a square lattice is obtained by numerical diagonalization. The eigenvalue spacing distribution and the spectral rigidity are analyzed. In non-integrable regimes we…

Condensed Matter · Physics 2009-10-28 Hendrik Meyer , Jean-Christian Anglès d'Auriac , Henrik Bruus

A model is proposed to study the possible pairing structures of N-boson systems with nonzero spin. Analytical solutions have been obtained. The emphasis is placed on the spin-structures of ground states with attractive or repulsive pairing…

Other Condensed Matter · Physics 2010-01-10 Chengguang Bao

We present a method to compute the magnetic susceptibility of spin systems at all temperatures in one and two dimensions. It relies on an approximation of the entropy versus energy (microcanonical potential function) on the whole range of…

Strongly Correlated Electrons · Physics 2015-06-22 B. Bernu , C. Lhuillier

The quantum dynamics of a localized spin-$\frac{1}{2} $ Particle interacting with an absorbing environment is investigated. The quantum Langevin-Schr\"odinger equation for spin-$\frac{1}{2} $ is obtained. The susceptibility function of the…

Quantum Physics · Physics 2015-11-04 Majid Amooshahi

Spin states of two-dimensional Wigner clusters are considered at low temperatures, when all electrons are in ground coordinate states. The spin subsystem behavior is determined by antiferromagnetic exchange integrals. The spin states in…

Mesoscale and Nanoscale Physics · Physics 2022-12-08 Mehrdad M. Mahmoodian , M. M. Mahmoodian , M. V. Entin

We determine the complete set of generalized spin squeezing inequalities. These are entanglement criteria that can be used for the experimental detection of entanglement in a system of spin-1/2 particles in which the spins cannot be…

Quantum Physics · Physics 2011-11-09 Geza Toth , Christian Knapp , Otfried Gühne , Hans J. Briegel

We study the spectral function of interacting one-dimensional fermions for an integrable lattice model away from half-filling. The divergent power-law singularity of the spectral function near the single-particle or single-hole energy is…

Strongly Correlated Electrons · Physics 2009-04-24 Rodrigo G. Pereira , Steven R. White , Ian Affleck

Determining the spectral density of a molecular system immersed in a proteomic scaffold and in contact to a solvent is a fundamental challenge in the coarse-grained description of, e.g., electron and energy transfer dynamics. Once the…

Quantum Physics · Physics 2014-11-04 Leonardo A. Pachon , Paul Brumer

The static and dynamic susceptibilities for a general class of mean field random orthogonal spherical spin glass models are studied. We show how the static and dynamical properties of the linear and nonlinear susceptibilities depend on the…

Disordered Systems and Neural Networks · Physics 2009-11-11 Leticia F. Cugliandolo , David S. Dean , Hajime Yoshino

The self-consistent inclusion of plasma effects in opacity calculations is a significant modeling challenge. As density increases, such effects can no longer be treated perturbatively. Building on a recently published model that addresses…

Plasma Physics · Physics 2024-10-08 C. E. Starrett , C. J. Fontes , H. B. Tran Tan , J. M. Kasper , J. R. White

Bragg scattering with linearly polarized light can be used to separately measure the density and the spin structure factor of a two spin component atomic gas by looking at the dependance of the scattering intensity on the polarization of…

Statistical Mechanics · Physics 2009-11-11 Iacopo Carusotto

State-space models are dynamical systems defined by a latent and an observed process. In ecology, stochastic state-space models in discrete time are most often used to describe the imperfectly observed dynamics of population sizes or animal…

Methodology · Statistics 2025-08-13 Frederic Barraquand , Julien Gibaud

Motivated by recent developments on large deviations in states of the spin chain, we reconsider the work of Petz, Raggio and Verbeure in 1989 on the variational expression of free energy density in the presence of a mean field type…

Mathematical Physics · Physics 2009-12-09 Fumio Hiai , Milan Mosonyi , Hiromichi Ohno , Denes Petz