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We consider a mixed dimensional elliptic partial differential equation posed in a bulk domain with a large number of embedded interfaces. In particular, we study well-posedness of the problem and regularity of the solution. We also propose…

Numerical Analysis · Mathematics 2023-01-02 Fredrik Hellman , Axel Målqvist , Malin Mosquera

We propose a fast impurity solver for the general quantum impurity model based on the perturbation theory around the atomic limit, which can be used in combination with the local density approximation (LDA) and the dynamical mean field…

Strongly Correlated Electrons · Physics 2009-11-10 Xi Dai , Kristjan Haule , Gabriel Kotliar

Semi-implicit time-stepping schemes for atmosphere and ocean models require elliptic solvers that work efficiently on modern supercomputers. This paper reports our study of the potential computational savings when using mixed precision…

Computational Physics · Physics 2022-10-05 Jan Ackmann , Peter D. Düben , Tim N. Palmer , Piotr K. Smolarkiewicz

We present a new approach to treat correlations in nonequilibrium quantum many-particle system. The method is based on ideas of configuration interaction theory of exact nonperturbative ground state electronic structure calculations. We use…

Mesoscale and Nanoscale Physics · Physics 2014-05-20 Alan A. Dzhioev , D. S. Kosov

Within a one particle approximation of the Dirac equation we investigate a defect system in a quantum wire. We demonstrate that by minimally coupling a laser field of frequency omega to such an impurity system, one may generate harmonics of…

Condensed Matter · Physics 2009-11-07 O. A. Castro-Alvaredo , A. Fring , C. Figueira de Morisson Faria

This paper introduces a machine learning approach to take a nonlinear differential-equation model that exhibits qualitative agreement with a physical experiment over a range of parameter values and produce a hybrid model that also exhibits…

Dynamical Systems · Mathematics 2022-08-24 K. H. Lee , D. A. W. Barton , L. Renson

In this paper, we present an adaptive algorithm to construct response surface approximations of high-fidelity models using a hierarchy of lower fidelity models. Our algorithm is based on multi-index stochastic collocation and automatically…

Numerical Analysis · Mathematics 2021-05-04 John D. Jakeman , Michael Eldred , Gianluca Geraci , Alex Gorodetsky

We incorporate explicit, non-perturbative treatment of spin-orbit coupling into ab initio auxiliary-field quantum Monte Carlo (AFQMC) calculations. The approach allows a general computational framework for molecular and bulk systems in…

Strongly Correlated Electrons · Physics 2023-02-16 Brandon Eskridge , Henry Krakauer , Hao Shi , Shiwei Zhang

A quantitative description of the excited electronic states of point defects and impurities is crucial for understanding materials properties, and possible applications of defects in quantum technologies. This is a considerable challenge…

Variational algorithms for strongly correlated chemical and materials systems are one of the most promising applications of near-term quantum computers. We present an extension to the variational quantum eigensolver that approximates the…

Quantum Physics · Physics 2020-08-26 William J. Huggins , Joonho Lee , Unpil Baek , Bryan O'Gorman , K. Birgitta Whaley

A variety of problems in device and materials design require the rapid forward modeling of Maxwell's equations in complex micro-structured materials. By combining high-order accurate integral equation methods with classical multiple…

Numerical Analysis · Mathematics 2011-04-29 Zydrunas Gimbutas , Leslie Greengard

We study the phase diagram of a twofold orbitally degenerate Anderson impurity model which presents a non-trivial fixed point similar to the two-impurity Kondo model one. Remarkably, this fixed point is more robust than the latter one,…

Strongly Correlated Electrons · Physics 2009-11-10 Michele Fabrizio , Andrew F. Ho , Lorenzo De Leo , Giuseppe E. Santoro

In this paper, we present a multiscale method for simulations of the multicontinua unsaturated flow problems in heterogeneous fractured porous media. The mathematical model is described by the system of Richards equations for each continuum…

Numerical Analysis · Mathematics 2019-08-02 Denis Spiridonov , Maria Vasilyeva , Eric T. Chung

An approach is proposed for evaluating dipolar and multipolar inter-site interactions in strongly correlated materials. This approach is based on the single-site dynamical mean-field theory (DMFT) in conjunction with the atomic…

Strongly Correlated Electrons · Physics 2016-09-13 L. V. Pourovskii

We demonstrate an algebraic construction of frequency-dependent bath orbitals which can be used in a robust and rigorously self-consistent DMFT-like embedding method, here called $\omega-$DMFT, suitable for use with Hamiltonian-based…

Strongly Correlated Electrons · Physics 2020-02-05 Max Nusspickel , George H. Booth

We implement the recently developed influence functional matrix product states approach as impurity solver in equilibrium and nonequilibrium dynamical mean field theory (DMFT) calculations of the single-band Hubbard model. The method yields…

Strongly Correlated Electrons · Physics 2025-07-02 Mithilesh Nayak , Julian Thoenniss , Michael Sonner , Dmitry A. Abanin , Philipp Werner

In multi-core quantum computing architectures, waveguide-mediated interconnects are essential for facilitating fast, high-fidelity quantum state transfer between qubits located in different chips. However, optimizing these systems typically…

We present a quantum-classical hybrid algorithm that simulates electronic structures of periodic systems such as ground states and quasiparticle band structures. By extending the unitary coupled cluster (UCC) theory to describe crystals in…

Quantum Physics · Physics 2022-02-16 Nobuyuki Yoshioka , Takeshi Sato , Yuya O. Nakagawa , Yu-ya Ohnishi , Wataru Mizukami

Starting from the random phase approximation for the weakly coupled multiband tightly-bounded electron systems, we calculate the dielectric matrix in terms of intraband and interband transitions. The advantages of this representation with…

Condensed Matter · Physics 2016-08-31 P. Zupanovic , A. Bjelis , S. Barisic

We present a classically solvable model that leads to optimized low-depth quantum circuits leveraging separable pair approximations. The obtained circuits are well suited as a baseline circuit for emerging quantum hardware and can, in the…

Quantum Physics · Physics 2022-04-07 Jakob S. Kottmann , Alán Aspuru-Guzik
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