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Solid state physics deals with systems composed of atoms with strongly bound electrons. The tunneling probability of each electron is determined by interactions that typically extend to neighboring sites, as their corresponding wave…

Materials Science · Physics 2019-11-27 F. Ramírez-Ramírez , E. Flores-Olmedo , G. Báez , E. Sadurní , R. ~A. Méndez-Sánchez

Studying the physics of quantum correlations has gained new interest after it has become possible to measure entanglement entropies of few body systems in experiments with ultracold atomic gases. Apart from investigating trapped atom…

Quantum Physics · Physics 2020-09-22 Arkadiusz Kuroś , Anna Okopińska

We develop a general framework for identifying phase reduced equations for finite populations of coupled oscillators that is valid far beyond the weak coupling approximation. This strategy represents a general extension of the theory from…

Adaptation and Self-Organizing Systems · Physics 2021-05-05 Youngmin Park , Dan Wilson

We present the quantum-selected configuration interaction-tailored coupled-cluster (QSCI-TCC) method, a hybrid quantum-classical scheme that tailors coupled-cluster (CC) theory with a quantum-selected configuration interaction (QSCI) wave…

Chemical Physics · Physics 2025-06-23 Luca Erhart , Yuichiro Yoshida , Wataru Mizukami

We present a near-linear scaling formulation of the explicitly-correlated coupled-cluster singles and doubles with perturbative triples method (CCSD(T)$_{\overline{\text{F12}}}$) for high-spin states of open-shell species. The approach is…

Chemical Physics · Physics 2024-07-30 Ashutosh Kumar , Frank Neese , Edward F. Valeev

The Hubbard model provides a simple framework in which one can study how certain aspects of the electronic structure of strongly interacting systems can be tuned to optimize the superconducting pairing correlations and how these changes…

Superconductivity · Physics 2022-03-02 Thomas A. Maier , Elbio Dagotto

This paper showed how a simple lumped parameter model of a circuit can yield correct quantum mechanical predictions of its behavior, even when there is quantum entanglement between components of that circuit. It addresses an important…

Quantum Physics · Physics 2017-12-21 Paul J. Werbos

The accuracy at which total energies of open-shell atoms and organic radicals may be calculated is assessed for selected coupled cluster perturbative triples expansions, all of which augment the coupled cluster singles and doubles (CCSD)…

Chemical Physics · Physics 2016-05-17 Janus Juul Eriksen , Devin A. Matthews , Poul Jørgensen , Jürgen Gauss

In this perspective, the various measures of electron correlation used in wavefunction theory, density functional theory and quantum information theory are briefly reviewed. We then focus on a more traditional metric based on dominant…

Chemical Physics · Physics 2023-04-07 Róbert Izsák , Aleksei V Ivanov , Nick S. Blunt , Nicole Holzmann , Frank Neese

Given an output wavefunction of a monitored quantum circuit consisting of both unitary gates and projective measurements, we ask whether two complementary subsystems are entangled or not. For Clifford circuits, we find that this question…

Quantum Physics · Physics 2021-09-21 Beni Yoshida

The aim of this work is to develop the relevant formalism for performing coupled-cluster (CC) calculations in nuclear matter and neutron star matter, including thereby important correlations to infinite order in the interaction and testing…

Nuclear Theory · Physics 2013-11-18 G. Baardsen , A. Ekström , G. Hagen , M. Hjorth-Jensen

Pair atomic density fitting (PADF) is a promising strategy to reduce the scaling with system size of quantum chemical methods for the calculation of the correlation energy like the direct random phase approximation (RPA) or second-order…

Chemical Physics · Physics 2023-03-14 Edoardo Spadetto , Pier Herman Theodoor Philipsen , Arno Förster , Lucas Visscher

We propose an optimal entanglement concentration protocol (ECP) for nonlocal N-electron systems in a partially entangled pure state, resorting to charge detection and the projection measurement on an additional electron. For each nonlocal…

Quantum Physics · Physics 2014-03-25 Bao-Cang Ren , Tie-Jun Wang , Ming Hua , Fu-Fu Du , Fu-Guo Deng

We combine the electron attachment (EA) and ionization potential (IP) equation-of-motion (EOM) coupled-cluster (CC) approaches with the CC($P$;$Q$) formalism. The resulting methodologies are used to describe the electronic states of several…

Chemical Physics · Physics 2025-09-19 Karthik Gururangan , Stephen H. Yuwono , A. Eugene DePrince , Piotr Piecuch

We discuss diagrammatic modifications to the coupled cluster doubles (CCD) equations, wherein different groups of terms out of rings, ladders, crossed-rings and mosaics can be removed to form approximations to the coupled cluster method, of…

Chemical Physics · Physics 2014-05-06 James J. Shepherd , Thomas. M. Henderson , Gustavo E. Scuseria

Quantum-chemical multi-configurational methods are required for a proper description of static electron correlation, a phenomenon inherent to the electronic structure of molecules with multiple (near-)degenerate frontier orbitals. Here, we…

Chemical Physics · Physics 2017-04-21 Christopher J. Stein , Markus Reiher

We report on our analysis of the Coulomb singularity problem in the frame of the coupled channel scattering theory including spin-orbit interaction. We assume that the coupling between the partial wave components involves orbital angular…

Materials Science · Physics 2015-04-06 Patrick Bogdanski , Henni Ouerdane

We proposed two linear optics based entanglement concentration protocols (ECPs) to obtain maximally entangled 4-mode Cluster-type entangled coherent state (ECS) from less (partially) entangled Cluster-type ECS. The first ECP is designed…

Quantum Physics · Physics 2019-02-05 Mitali Sisodia , Chitra Shukla , Gui-Lu Long

We develop an approach to study the entanglement in two coupled harmonic oscillators. We start by introducing an unitary transformation to end up with the solutions of the energy spectrum. These are used to construct the corresponding…

Quantum Physics · Physics 2015-05-28 Ahmed Jellal , Fethi Madouri , Abdeldjalil Merdaci

Coupled-cluster theory is a powerful tool for first-principles calculations of atomic nuclei, enabling accurate predictions of nuclear observables across the Segr\`e chart. While coupled-cluster computations are especially efficient at…

Nuclear Theory · Physics 2026-04-08 F. Marino , F. Bonaiti , P. Demol , S. Bacca , T. Duguet , G. Hagen , G. R. Jansen , T. Papenbrock , A. Tichai