English
Related papers

Related papers: Secondly quantized multi-configurational approach …

200 papers

Efficient representations of the Hamiltonian such as double factorization drastically reduce circuit depth or number of repetitions in error corrected and noisy intermediate scale quantum (NISQ) algorithms for chemistry. We report a…

A new method for calculation of shell model intrinsic density matrices, defined as two-particle density matrices integrated over the centre-of-mass position vector of two last particles and complemented with isospin variables, has been…

Nuclear Theory · Physics 2007-05-23 A. Deveikis , G. Kamuntavicius

A new method is presented to generate atomic structures that reproduce the essential characteristics of arbitrary material systems, phases, or ensembles. Previous methods allow one to reproduce the essential characteristics (e.g. chemical…

Materials Science · Physics 2024-09-24 James M. Goff , Coreen Mullen , Shizhong Yang , Oleg N. Starovoytov , Mitchell A. Wood

The application of quantum computing to data management has attracted growing interest, yet remains constrained by a limited understanding of how the physical behaviour of quantum devices relates to the structure and difficulty of database…

Quantum Physics · Physics 2026-05-15 Wolfgang Mauerer , Manuel Schönberger

When the $q$-deformed creation and annihilation operators are used in a second quantization procedure, the algebra satisfied by basis vectors (orthogonal complete set) should be also deformed such as a field operator remains invariant under…

High Energy Physics - Theory · Physics 2017-02-01 Kazuhiko Odaka

We develop a new formalism to treat nuclear many-body systems using bare nucleon-nucleon interaction. It has become evident that the tensor interaction plays important role in nuclear many-body systems due to the role of the pion in…

Nuclear Theory · Physics 2017-04-28 Takayuki Myo , Hiroshi Toki , Kiyomi Ikeda , Hisashi Horiuchi , Tadahiro Suhara

This paper summarizes a research program that has been underway for a decade. The objective is to find a fast and accurate scheme for solving quantum problems which does not involve a Monte Carlo algorithm. We use an alternative strategy…

High Energy Physics - Phenomenology · Physics 2007-05-23 Carl M. Bender , Lawrence R. Mead , Kimball A. Milton

Second quantization has been widely used in quantum mechanics and quantum chemistry, which is trivial and error-prone for researchers. Fortunately it is a good candidate for automatic evaluation with its simple, trivial and intrinsic…

Quantum Physics · Physics 2017-07-12 Xinle Liu

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific investigations. Using the "Sender-Receiver" model, we propose quantum algorithms for matrix operations such as matrix-vector product,…

Quantum Physics · Physics 2024-03-11 Wentao Qi , Alexandr I. Zenchuk , Asutosh Kumar , Junde Wu

A finite element methodology for large classes of variational boundary value problems is defined which involves discretizing two linear operators: (1) the differential operator defining the spatial boundary value problem; and (2) a Riesz…

Numerical Analysis · Mathematics 2017-12-08 Brendan Keith , Socratis Petrides , Federico Fuentes , Leszek Demkowicz

In this article, we present a set of hierarchy Bloch equations for the reduced density operators in either canonical or grand canonical ensembles in the occupation number representation. They provide a convenient tool for studying the…

Statistical Mechanics · Physics 2009-11-10 Liqiang Wei , C. C. Sun

The aim of this work is to present an overview of the derivation of the effective shell-model Hamiltonian and decay operators within many-body perturbation theory, and to show the results of selected shell-model studies based on their…

Nuclear Theory · Physics 2020-10-19 L. Coraggio , N. Itaco

The regular structures obtained by optical lattice technology and their behaviour are analysed from the quantum information perspective. Initially, we demonstrate that a triangular optical lattice of two atomic species, bosonic or…

In the framework of solid mechanics, the task of deriving material parameters from experimental data has recently re-emerged with the progress in full-field measurement capabilities and the renewed advances of machine learning. In this…

Computational Engineering, Finance, and Science · Computer Science 2026-01-27 Ulrich Römer , Stefan Hartmann , Jendrik-Alexander Tröger , David Anton , Henning Wessels , Moritz Flaschel , Laura De Lorenzis

On the example of stationary states of a system consisting of an atom and a quantized electromagnetic field (the Jaynes-Cummings model in free space), it is shown that the physical characteristics of the system (as the energy and the…

Quantum Physics · Physics 2019-05-14 Atom Zh. Muradyan , Gevorg Muradyan

Density matrix perturbation theory [Phys. Rev. Lett. Vol. 92, 193001 (2004)] provides an efficient framework for the linear scaling computation of response properties [Phys. Rev. Lett. Vol. 92, 193002 (2004)]. In this article, we generalize…

Computational Physics · Physics 2009-11-11 Anders M. N. Niklasson , Valery Weber , Matt Challacombe

We have found a (dense) basis for the N-representable, two-electron densities, in which all N-representable two-electron densities can be expanded, using positive coefficients. The inverse problem of finding a representative wavefunction,…

Strongly Correlated Electrons · Physics 2009-11-10 Mats-Erik Pistol

Given two unsorted lists each of length N that have a single common entry, a quantum computer can find that matching element with a work factor of $O(N^{3/4}\log N)$ (measured in quantum memory accesses and accesses to each list). The…

Quantum Physics · Physics 2007-05-23 Mark Heiligman

We show that from the point of view of the generalized pairing Hamiltonian, the atomic nucleus is a system with small entanglement and can thus be described efficiently using a 1D tensor network (matrix-product state) despite the presence…

Nuclear Theory · Physics 2024-03-07 Roman Rausch , Cassian Plorin , Matthias Peschke , Christoph Karrasch

We present a theoretical framework based on second quantization in Liouville space to treat open quantum systems. We consider an ensemble of identical quantum emitters characterized by a discrete set of quantum states. The second…

Quantum Physics · Physics 2023-12-12 V. Sukharnikov , S. Chuchurka , A. Benediktovitch , N. Rohringer