English
Related papers

Related papers: The Quantum Energy Density: Improved Efficiency fo…

200 papers

Cloud-based quantum computers do not provide users with access to hardware-level information such as the underlying Hamiltonians, which obstructs the characterization of their physical properties. We propose a method to infer the energy…

Quantum Physics · Physics 2025-12-18 Nobumasa Ishida , Yoshihiko Hasegawa

Uniform neutron matter is approximated by a cubic box containing a finite number of neutrons, with periodic boundary conditions. We report variational and Green's function Monte Carlo calculations of the ground state of fourteen neutrons in…

Nuclear Theory · Physics 2009-11-10 J. Carlson , J. Morales , V. R. Pandharipande , D. G. Ravenhall

The diagonalization of the metrical and canonical Hamilton operators of a scalar field with an arbitrary coupling, with a curvature in N-dimensional homogeneous isotropic space is considered in this paper. The energy spectrum of the…

General Relativity and Quantum Cosmology · Physics 2011-04-20 Yu. V. Pavlov

Determining ground state energies of quantum systems by hybrid classical/quantum methods has emerged as a promising candidate application for near-term quantum computational resources. Short of large-scale fault-tolerant quantum computers,…

Quantum Physics · Physics 2016-10-25 Nicholas C. Rubin

Quantum Monte Carlo (QMC) is a powerful method to calculate accurate energies and forces for molecular systems. In this work, we demonstrate how we can obtain accurate QMC forces for the fluxional ethanol molecule at room temperature by…

A computational model is presented to calculate the ground state energy of neutral and charged excitons confined in semiconductor quantum dots. The model is based on the variational Quantum Monte Carlo method and effective mass…

Mesoscale and Nanoscale Physics · Physics 2021-02-03 Josep Planelles , Juan I. Climente

We propose and benchmark a Gross-Pitaevskii-like equation for two-component Bose mixtures with competing interactions in 1D. Our approach follows the density-functional theory with the energy functional based on the exact Quantum Monte…

Quantum Gases · Physics 2023-04-26 Jakub Kopyciński , Luca Parisi , Nick G. Parker , Krzysztof Pawłowski

We derive a lattice approximation for a class of equilibrium quantum statistics describing the behaviour of any combination and number of bosonic and fermionic particles with any sufficiently binding potential. We then develop an intuitive…

Statistical Mechanics · Physics 2008-11-26 Jani Lukkarinen

There are several definitions of energy density in quantum mechanics. These yield expressions that differ locally, but all satisfy a continuity equation and integrate to the value of the expected energy of the system under consideration.…

Quantum Physics · Physics 2023-06-29 Francisco Torres Arvizu , Adrian Ortega , Hernán Larralde

Quantum Monte Carlo (QMC) is an advanced simulation methodology for studies of manybody quantum systems. In this review, we focus on the electronic structure QMC, i.e., methods relevant for systems described by the electron-ion…

Other Condensed Matter · Physics 2010-08-16 Michal Bajdich , Lubos Mitas

How much energy does a quantum computer consume? Are they more efficient than their classical counterparts? In this work, we make a step towards answering these questions. We define the energy efficiency of a quantum computer as the ratio…

We propose a method to decompose the total energy of a supercell containing defects into contributions of individual atoms, using the energy density formalism within density functional theory. The spatial energy density is unique up to a…

Materials Science · Physics 2011-04-20 Min Yu , Dallas R. Trinkle , Richard M. Martin

Quantum computing has been increasingly applied in nuclear physics. In this work, we combine quantum computing with the complex scaling method to address the resonance problem. Due to the non-Hermiticity introduced by complex scaling,…

Nuclear Theory · Physics 2024-09-11 Hantao Zhang , Dong Bai , Zhongzhou Ren

Variational ab-initio methods in quantum chemistry stand out among other methods in providing direct access to the wave function. This allows in principle straightforward extraction of any other observable of interest, besides the energy,…

We present a straightforward method for obtaining exact classical and quantum molecular Hamiltonians in terms of arbitrary coordinates. As compared to other approaches the resulting expression are rather compact, the physical meaning of…

Chemical Physics · Physics 2009-11-13 Yonggang Yang , Oliver Kühn

This paper derives and demonstrates a new, purely density-based ab initio approach for calculation of the energies and properties of many-electron systems. It is based upon the discovery of relationships that govern the "mechanics" of the…

Chemical Physics · Physics 2024-09-04 James C. Ellenbogen

An efficient scheme is introduced for a fast and smooth convergence to the thermodynamic limit with finite size cluster calculations. This is obtained by modifying the energy levels of the non interacting Hamiltonian in a way consistent…

Strongly Correlated Electrons · Physics 2015-05-12 Sandro Sorella

The binding energies of n < 100 carbon clusters are calculated using the ab-initio density functional theory code Quantum Espresso. Carbon cluster geometries are determined using several levels of classical techniques and further refined…

Solar and Stellar Astrophysics · Physics 2015-06-23 Christopher Mauney , Marco Buongiorno Nardelli , Davide Lazzati

We derive expressions for the expectation values of the local energy and the local power transferred by an external electrical field to a many-particle system of interacting spinless electrons. In analogy with the definition of the (local)…

Quantum Physics · Physics 2016-06-22 Guillermo Albareda , Fabio Lorenzo Traversa , Xavier Oriols

While most work on the quantum simulation of chemistry has focused on computing energy surfaces, a similarly important application requiring subtly different algorithms is the computation of energy derivatives. Almost all molecular…