English
Related papers

Related papers: Open source FCI code for quantum dots and effectiv…

200 papers

Finding the ground state of a fermionic Hamiltonian using quantum Monte Carlo is a very difficult problem, due to the Fermi sign problem. While still scaling exponentially, full configuration-interaction Monte Carlo (FCI-QMC) mitigates some…

Computational Physics · Physics 2013-12-17 Michael H. Kolodrubetz , Bryan K. Clark

In the present letter, it is demonstrated how full configuration interaction (FCI) results in extended basis sets may be obtained to within sub-kJ/mol accuracy by decomposing the energy in terms of many-body expansions in the virtual…

Chemical Physics · Physics 2017-09-15 Janus J. Eriksen , Filippo Lipparini , Jürgen Gauss

We introduce the pCI software package for high-precision atomic structure calculations. The standard method of calculation is based on the configuration interaction (CI) method to describe valence correlations, but can be extended to attain…

In a previous work (arXiv:2010.02027) we showed how the full configuration interaction (FCI) ground state energy can be obtained as a functional of an arbitrary reference wavefunction by means of a gradient descent or quasi-Newton…

Chemical Physics · Physics 2020-12-10 Carlos A. Jiménez-Hoyos

We present the first version of the QEngine, an open-source C++ library for simulating and controlling ultracold quantum systems using optimal control theory (OCT). The most notable systems presented here are Bose-Einstein condensates,…

Quantum Physics · Physics 2019-07-24 Jens Jakob Sørensen , Jesper Jensen , Till Heinzel , Jacob Sherson

Coupled cluster (CC) theory is often considered the gold standard of quantum-chemistry. For solids, however, the available software is scarce. We present CC-aims, which can interface ab initio codes with localized atomic orbitals and the CC…

Materials Science · Physics 2022-04-14 Evgeny Moerman , Felix Hummel , Andreas Grüneis , Andreas Irmler , Matthias Scheffler

We present a stable and systematically improvable quantum Monte Carlo (QMC) approach to calculating excited-state energies, which we implement using our fast randomized iteration method for the full configuration interaction problem…

Computational Physics · Physics 2023-10-03 Samuel M. Greene , Robert J. Webber , James E. T. Smith , Jonathan Weare , Timothy C. Berkelbach

Doubly occupied configuration interaction (DOCI), the exact diagonalization of the Hamiltonian in the paired (seniority zero) sector of the Hilbert space, is a combinatorial cost wave function that can be very efficiently approximated by…

Chemical Physics · Physics 2020-05-14 Jacob M. Wahlen-Strothman , Thomas M. Henderson , Gustavo E. Scuseria

We present an open source kinematic fitting routine designed for low-energy nuclear physics applications. Although kinematic fitting is commonly used in high-energy particle physics, it is rarely used in low-energy nuclear physics, despite…

Instrumentation and Detectors · Physics 2019-11-26 R. Smith , J. Bishop

We present the TRIQS library, a Toolbox for Research on Interacting Quantum Systems. It is an open-source, computational physics library providing a framework for the quick development of applications in the field of many-body quantum…

Strongly Correlated Electrons · Physics 2016-09-12 Olivier Parcollet , Michel Ferrero , Thomas Ayral , Hartmut Hafermann , Igor Krivenko , Laura Messio , Priyanka Seth

We introduce a family of methods for the full configuration interaction problem in quantum chemistry, based on the fast randomized iteration (FRI) framework [L.-H. Lim and J. Weare, SIAM Rev. 59, 547 (2017)]. These methods, which we term…

Chemical Physics · Physics 2023-09-25 Samuel M. Greene , Robert J. Webber , Jonathan Weare , Timothy C. Berkelbach

We present a framework for efficiently performing Monte Carlo wave-function simulations in cavity QED with moving particles. It relies heavily on the object-oriented programming paradigm as realised in C++, and is extensible and applicable…

Quantum Physics · Physics 2009-11-13 A. Vukics , H. Ritsch

Asynchronous Many-Task Systems (AMTs) exhibit different communication patterns from traditional High-Performance Computing (HPC) applications, characterized by asynchrony, concurrency, and multithreading. Existing communication libraries…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-03-20 Jiakun Yan , Marc Snir

Full configuration interaction (FCI) solvers are limited to small basis sets due to their expensive computational costs. An optimal orbital selection for FCI (OptOrbFCI) is proposed to boost the power of existing FCI solvers to pursue the…

Chemical Physics · Physics 2020-09-01 Yingzhou Li , Jianfeng Lu

Using finite basis sets, it is shown how to construct a local Hamiltonian, such that one of its infinitely many degenerate eigenfunctions is the ground state full configuration interaction (FCI) wave function in that basis set. Formally,…

Chemical Physics · Physics 2010-10-04 Daniel R. Rohr , Andreas Savin

Facilitated by a rigorous partitioning of a molecular system's orbital basis into two fundamental subspaces - a reference and an expansion space, both with orbitals of unspecified occupancy - we generalize our recently introduced many-body…

Chemical Physics · Physics 2019-12-12 Janus J. Eriksen , Jürgen Gauss

According to the modern paradigms of software engineering, standard tasks are best accomplished by reusable open source libraries. We describe OpenOrbitalOptimizer: a reusable open source C++ library for the iterative solution of coupled…

Computational Physics · Physics 2025-06-03 Susi Lehtola , Lori A. Burns

With the potential of quantum algorithms to solve intractable classical problems, quantum computing is rapidly evolving and more algorithms are being developed and optimized. Expressing these quantum algorithms using a high-level language…

Quantum Physics · Physics 2020-05-28 N. Khammassi , I. Ashraf , J. v. Someren , R. Nane , A. M. Krol , M. A. Rol , L. Lao , K. Bertels , C. G. Almudever

The dual fermion method is a multiscale approach for solving lattice problems of interacting strongly correlated systems. In this paper, we present the \texttt{opendf} code, an open-source implementation of the dual fermion method…

Strongly Correlated Electrons · Physics 2015-10-14 Andrey E. Antipov , James P. F. LeBlanc , Emanuel Gull

\textsc{Quantum Package} is an open-source programming environment for quantum chemistry specially designed for wave function methods. Its main goal is the development of determinant-driven selected configuration interaction (sCI) methods…