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Related papers: Improved variational approach to the two-site Bose…

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We revisit the one-dimensional attractive Hubbard model by using the Bethe-ansatz based density-functional theory and density-matrix renormalization method. The ground-state properties of this model are discussed in details for different…

The Bose-Hubbard Hamiltonian can be simplified to have only two lattice sites, in which case the system being described is referred to as a dimer. Due to its structure, the hopping term of the dimer Hamiltonian enjoys invariance in a family…

Quantum Physics · Physics 2026-05-07 Madeline Berezowski , Artur Sowa , Jonas Fransson

The chaotic phase of the tilted Bose-Hubbard model is identified as a function of energy, tilt strength and particle interaction, from the eigenstate structure and the statistical features of the energy spectrum. Our analysis reveals that…

Quantum Physics · Physics 2026-05-08 Pilar Martín Clavero , Alberto Rodríguez

We revisit the two-site Hubbard-Holstein model by using extended phonon coherent states. The nontrivial singlet bipolaron is studied exactly in the whole coupling regime. The ground-state (GS) energy and the double occupancy probability are…

Strongly Correlated Electrons · Physics 2015-05-13 Yu-Yu Zhang , Tao Liu , Qing-Hu Chen , Xiaoguang Wang , Kelin Wang

The preparation of quantum states using short quantum circuits is one of the most promising near-term applications of small quantum computers, especially if the circuit is short enough and the fidelity of gates high enough that it can be…

Quantum Physics · Physics 2015-10-07 D. Wecker , M. B. Hastings , M. Troyer

By revisiting the path-integral formulation of the Hubbard model, we propose a theoretical approach based on a semiclassical approximation employing an unconventional coherent-state representation. Within this framework, a subset of the…

Strongly Correlated Electrons · Physics 2026-04-06 Yuki Yamasaki , Hidemaro Suwa , Cristian D. Batista , Shintaro Hoshino

We present a variational method for approximating the ground state of spin models close to (Richardson-Gaudin) integrability. This is done by variationally optimizing eigenstates of integrable Richardson-Gaudin models, where the toolbox of…

Strongly Correlated Electrons · Physics 2017-12-11 Pieter W. Claeys , Jean-Sébastien Caux , Dimitri Van Neck , Stijn De Baerdemacker

We construct a basis for the many-particle ground states of the positive hopping Bose-Hubbard model on line graphs of finite 2-connected planar bipartite graphs at sufficiently low filling factors. The particles in these states are…

Statistical Mechanics · Physics 2012-05-30 Johannes Motruk , Andreas Mielke

We benchmark the accuracy of a variational quantum eigensolver based on a finite-depth quantum circuit encoding ground state of local Hamiltonians. We show that in gapped phases, the accuracy improves exponentially with the depth of the…

Bosonic two-ring ladders constitute an important class of atomtronic circuits, where coherent current flows not only can offer a new insight into many-body physics, but also can play the role of actual degrees of freedom, and hence allow…

Quantum Gases · Physics 2021-05-25 Albert Escrivà , Andrea Richaud , Bruno Juliá-Díaz , Montserrat Guilleumas

The ground state phase diagram of the extended Hubbard model containing nearest and next-to-nearest neighbor interactions is investigated in the thermodynamic limit using an exact method. It is found that taking into account local…

Strongly Correlated Electrons · Physics 2009-10-31 Zsolt Szabo

We consider a variational model for two interacting species (or phases), subject to cross and self attractive forces. We show existence and several qualitative properties of minimizers. Depending on the strengths of the forces, different…

Analysis of PDEs · Mathematics 2015-07-31 Marco Cicalese , Lucia De Luca , Matteo Novaga , Marcello Ponsiglione

The Hubbard model has occupied the minds of condensed matter physicists for most part of the last century. This model provides insight into a range of phenomena in correlated electron systems. We wish to examine the paradigm of quantum…

Quantum Physics · Physics 2026-05-12 Kunal Vyas , Fengping Jin , Hans De Raedt , Kristel Michielsen

This work introduces a novel approach to quantum simulation by leveraging continuous-variable systems within a photonic hardware-inspired framework. The primary focus is on simulating static properties of the ground state of Hamiltonians…

This paper considers the problem of computing Bayesian estimates of both states and model parameters for nonlinear state-space models. Generally, this problem does not have a tractable solution and approximations must be utilised. In this…

Machine Learning · Statistics 2020-12-15 Jarrad Courts , Johannes Hendriks , Adrian Wills , Thomas Schön , Brett Ninness

The dynamical evolution of a two-site Hubbard model is derived in the presence of an uniform external magnetic field for a general initial state. The time evolution of the half-filled (two-particle) case has a complex behaviour. Under…

Condensed Matter · Physics 2007-05-23 A. T. Costa , M. T. Thomaz

We propose a variational approximation to the ground state energy of a one-dimensional gas of interacting bosons on the continuum based on the Bethe Ansatz ground state wavefunction of the Lieb-Liniger model. We apply our variational…

Quantum Gases · Physics 2020-01-08 S. De Palo , R. Citro , E. Orignac

We present a scheme to perform an iterative variational optimization with infinite projected entangled-pair states (iPEPS), a tensor network ansatz for a two-dimensional wave function in the thermodynamic limit, to compute the ground state…

Strongly Correlated Electrons · Physics 2017-05-02 Philippe Corboz

The study of entanglement between bosonic systems is of primary importance for establishing feasible resources needed for implementing quantum information protocols, both in their interacting atomic or photonic realizations. Atomic systems…

Quantum Physics · Physics 2014-12-31 Fabio Gentile , Arianna Montorsi , Marco Roncaglia

We present a generalization of the variational principle that is compatible with any Hamiltonian eigenstate that can be specified uniquely by a list of properties. This variational principle appears to be compatible with a wide range of…

Chemical Physics · Physics 2020-02-07 Jacqueline A. R. Shea , Elise Gwin , Eric Neuscamman