Work

Benchmarking the Variational Reduced Density Matrix Theory in the Doubly Occupied Configuration Interaction Space with Integrable Pairing Models

Year: 2018

Type: article

Abstract: The variational reduced density matrix theory has been recently applied with great success to models within the truncated doubly occupied configuration interaction space, which corresponds to the seniority zero subspace. Conservation of the seniority quantum number restricts the Hamiltonians to be based on the SU(2) algebra. Among them there is a whole family of exactly solvable Richardson-Gaudin pairing Hamiltonians. We benchmark the variational theory against two different exactly solvable models, the Richardson-Gaudin-Kitaev and the reduced BCS Hamiltonians. We obtain exact numerical results for the so-called [Formula: see text] N-representability conditions in both cases for systems that go from 10 to 100 particles. However, when random single-particle energies as appropriate for small superconducting grains are considered, the exactness is lost but still a high accuracy is obtained.

Source: Journal of Chemical Theory and Computation

DOI: 10.1021/acs.jctc.8b00387

Authors: A. Rubio-García, D. R. Alcoba, P. Capuzzi, J. Dukelsky

Institutions: Consejo Superior de Investigaciones Científicas, Instituto de Estructura de la Materia, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Instituto de Física de Buenos Aires

Language: English

Topic: Advanced Chemical Physics Studies

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Consejo Nacional de Investigaciones Científicas y Técnicas, Ministerio de Economía y Competitividad, Universidad de Buenos Aires, European Regional Development Fund