AI Article Synopsis
- The study examines the stability of a two-component Bose-Einstein condensate (BEC) when the classical version shows regular motion.
- It focuses on fidelity as a measure of stability for various initial quantum states, particularly Fock states with specific atom counts in each component.
- The findings suggest that Fock states with all atoms in one component can be more stable at certain times compared to those with a mix in both components, and an experimental approach to measure this fidelity directly is proposed.
Article Abstract
We study the stability of a two-component Bose-Einstein condensate (BEC) in the parameter regime in which its classical counterpart has regular motion. The stability is characterized by the fidelity for both the same and different initial states. We study as initial states the Fock states with definite numbers of atoms in each component of the BEC. It is found that for some initial times the two Fock states with all the atoms in the same component of the BEC are more stable than Fock states with atoms distributed in the two components. An experimental scheme is discussed, in which the fidelity can be measured in a direct way.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevE.77.056218 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Carbon Doping in Small Lithium Clusters: Structural, Energetic, and Electronic Properties from Quantum Monte Carlo Calculations.
ACS Omega
January 2025
Instituto de Física, Universidade Federal de Goiás, Goiânia, Goiás 74001-970, Brazil.
We investigate the energetic and structural properties of small lithium clusters doped with a carbon atom using a combination of computational methods, including density functional theory (DFT), diffusion quantum Monte Carlo (DMC), and the Hartree-Fock (HF) approximation. We calculate the lowest energy structures, total ground-state energies, electron populations, binding energies, and dissociation energies as a function of cluster size. Our results show that carbon doping significantly enhances the stability of lithium clusters, increasing the magnitude of the binding energy by 0.
View Article and Find Full Text PDFAccelerating Fock Build via Hybrid Analytical-Numerical Integration.
J Phys Chem A
January 2025
Qingdao Institute for Theoretical and Computational Sciences and Center for Optics Research and Engineering, Shandong University, Qingdao 266237, P. R. China.
A hybrid analytical-numerical integration scheme is introduced to accelerate the Fock build in self-consistent field (SCF) and time-dependent density functional theory (TDDFT) calculations. To evaluate the Coulomb matrix [], the density matrix is first decomposed into two parts, the superposition of atomic density matrices and the rest = -. While [] is evaluated analytically, [] is evaluated fully numerically [with the multipole expansion of the Coulomb potential (MECP)] during the SCF iterations.
View Article and Find Full Text PDFIntroducing GPU Acceleration into the Python-Based Simulations of Chemistry Framework.
J Phys Chem A
January 2025
Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
We introduce the first version of GPU4PySCF, a module that provides GPU acceleration of methods in PySCF. As a core functionality, this provides a GPU implementation of two-electron repulsion integrals (ERIs) for contracted basis sets comprising up to functions using the Rys quadrature. As an illustration of how this can accelerate a quantum chemistry workflow, we describe how to use the ERIs efficiently in the integral-direct Hartree-Fock build and nuclear gradient construction.
View Article and Find Full Text PDFThe divide expand consolidate scheme for unrestricted second order Møller-Plesset perturbation theory ground state energies.
J Chem Phys
January 2025
Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830, USA.
The linear scaling divide-expand-consolidate (DEC) framework is expanded to include unrestricted Hartree-Fock references. By partitioning the orbital space and employing local molecular orbitals, the full molecular calculation can be performed as independent calculations on individual fragments, making the method well-suited for massively parallel implementations. This approach also incorporates error control through the fragment optimization threshold (FOT), which maintains precision and consistency throughout the calculations.
View Article and Find Full Text PDFExtending Density-Corrected Density Functional Theory to Large Molecular Systems.
J Phys Chem Lett
January 2025
Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea.
Practical density-corrected density functional theory (DC-DFT) calculations rely on Hartree-Fock (HF) densities, which can be computationally expensive for systems with over a hundred atoms. We extend the applicability of HF-DFT using the dual-basis method, where the density matrix from a smaller basis set is used to estimate the HF solution on a larger basis set. Benchmarks on many systems, including the GMTKN55 database for main-group chemistry, and the L7 and S6L data sets for large molecular systems demonstrate the efficacy of our approach.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!