English
Related papers

Related papers: Variational cluster approach to the single impurit…

200 papers

The unitary coupled cluster (UCC) approximation is one of the more promising wave-function ans\"atze for electronic structure calculations on quantum computers via the variational quantum eigensolver algorithm. However, for large systems…

Quantum Physics · Physics 2021-09-30 Jia Chen , Hai-Ping Cheng , James K. Freericks

A model of a randomly disordered system with site-diagonal random energy fluctuations is introduced. It is an extension of Wegner's $n$-orbital model to arbitrary eigenvalue distribution in the electronic level space. The new feature is…

Condensed Matter · Physics 2009-10-22 Peter Neu , Roland Speicher

We introduce a variational implementation of cluster perturbation theory (CPT) to address the dynamics of spin systems driven out of equilibrium. We benchmark the method with the quantum Ising model subject to a sudden quench of the…

Strongly Correlated Electrons · Physics 2016-12-07 Mohammad Zhian Asadzadeh , Michele Fabrizio , Enrico Arrigoni

We introduce a method to obtain the specific heat of quantum impurity models via a direct calculation of the impurity internal energy requiring only the evaluation of local quantities within a single numerical renormalization group (NRG)…

Strongly Correlated Electrons · Physics 2012-08-29 L. Merker , T. A. Costi

We present a hybrid classical-quantum computing paradigm where the quantum part strictly runs within the coherence time of a quantum annealer, a method we call variational coherent quantum annealing (VCQA). It involves optimizing the…

Quantum Physics · Physics 2023-10-04 N. Barraza , G. Alvarado Barrios , I. Montalban , E. Solano , F. Albarrán-Arriagada

Coupled cluster theory provides hierarchical many-particle models and is presently considered as the ultimate benchmark in quantum chemistry. Despite is practical significance, a rigorous mathematical analysis of its properties is still in…

Mathematical Physics · Physics 2018-01-24 Heinz-Jürgen Flad , Gohar Flad-Harutyunyan

The non-crossing approximation (NCA) is generalized for the Anderson model with finite Coulomb repulsion U. Resummation of infinite number of terms is performed so as to incorporate all leading contributions in the limit of large degeneracy…

Strongly Correlated Electrons · Physics 2007-05-23 J. Otsuki , Y. Kuramoto

Recently solvers for the Anderson impurity model (AIM) working directly on the real-frequency axis have gained much interest. A simple and yet frequently used impurity solver is exact diagonalization (ED), which is based on a discretization…

Strongly Correlated Electrons · Physics 2017-10-24 Manuel Zingl , Martin Nuss , Daniel Bauernfeind , Markus Aichhorn

We investigate dynamics of a single mobile impurity immersed in a bath of Anderson localized particles and focus on the regime of relatively strong disorder and interactions. In that regime, the dynamics of the system is particularly slow,…

Disordered Systems and Neural Networks · Physics 2024-03-07 Piotr Sierant , Titas Chanda , Maciej Lewenstein , Jakub Zakrzewski

We present a mapping between the Edwards model of disorder describing the motion of a single particle subject to randomly-positioned static scatterers and the Bose polaron problem of a light quantum impurity interacting with a Bose-Einstein…

Quantum Gases · Physics 2022-02-07 Félix Rose , Richard Schmidt

We demonstrate the effectiveness of a generalized renormalized perturbational approach to calculate the induced magnetization for the single impurity Anderson model with a strong on-site interaction, using flow equations for renormalized…

Strongly Correlated Electrons · Physics 2013-04-30 K. Edwards , A. C. Hewson , V. Pandis

Using an extended Anderson/Kondo impurity model to describe the magnetic moments around an impurity doped in high-$T_{\text{c}}$ d-wave cuprates and in the framework of the slave-boson meanfield approach, we study numerically the impurity…

Superconductivity · Physics 2009-11-07 Q. Han , Z. D. Wang , X. -G. Li , L. -Y. Zhang

The Anderson model for a magnetic impurity in a one-dimensional quasicrystal is studied using the numerical renormalization group (NRG). The main focus is elucidating the physics at the critical point of the Aubry-Andre (AA) Hamiltonian,…

Strongly Correlated Electrons · Physics 2023-03-21 Ang-Kun Wu , Daniel Bauernfeind , Xiaodong Cao , Sarang Gopalakrishnan , Kevin Ingersent , J. H. Pixley

Monoclonal antibody solutions are set to become a major therapeutic tool in the years to come, capable of targeting various diseases by clever designing their antigen binding site. However, the formulation of stable solutions suitable for…

Single-particle dynamics of the Anderson impurity model in the presence of a magnetic field $H$ are considered, using a recently developed local moment approach that encompasses all energy scales, field and interaction strengths. For strong…

Strongly Correlated Electrons · Physics 2009-11-07 David E. Logan , Nigel L. Dickens

Using the cumulant Green's functions method (CGFM), we study the single impurity Anderson model (SIAM). The CGFM starting point is a diagonalization of the SIAM Hamiltonian expressed in a semi-chain form, containing N sites, viz., a…

Strongly Correlated Electrons · Physics 2024-09-26 T. M. Sobreira , T. O. Puel , M. A. Manya , S. E. Ulloa , G. B. Martins , J. Silva-Valencia , R. N. Lira , M. S. Figueira

We develop a continuous-time quantum Monte Carlo method based on a strong-coupling expansion for Anderson impurity models with phonon-assisted hybridizations for arbitrary number of phonon modes. As a benchmark, we investigate the…

Strongly Correlated Electrons · Physics 2015-06-15 Kazumasa Hattori

We study in this work the dynamics of a granular impurity immersed in a low-density granular gas of identical particles. For description of the kinetics of the granular gas and the impurity particles we use the rough hard sphere collisional…

Soft Condensed Matter · Physics 2017-07-13 Francisco Vega Reyes , Antonio Lasanta , Andrés Santos , Vicente Garzó

We develop a diagrammatic Monte Carlo method for the real-time dynamics of dissipative quantum impurity models. These are small open quantum systems with interaction and local Markovian dissipation, coupled to a large quantum bath. Our…

Strongly Correlated Electrons · Physics 2024-03-26 Matthieu Vanhoecke , Marco Schirò

We discuss a clustering method for Gaussian mixture model based on the sparse principal component analysis (SPCA) method and compare it with the IF-PCA method. We also discuss the dependent case where the covariance matrix $\Sigma$ is not…

Methodology · Statistics 2016-02-18 T. Tony Cai , Linjun Zhang