Functional approach for pairing in finite systems: How to define restoration of broken symmetries in Energy Density Functional theory ?

Guillaume Hupin; Denis Lacroix; Michael Bender

doi:10.1088/1742-6596/321/1/012056

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arXiv · 1105.5892

Functional approach for pairing in finite systems: How to define restoration of broken symmetries in Energy Density Functional theory ?

Guillaume Hupin·Denis Lacroix·Michael Bender

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Abstract

The Multi-Reference Energy Density Functional (MR-EDF) approach (also called configuration mixing or Generator Coordinate Method), that is commonly used to treat pairing in finite nuclei and project onto particle number, is re-analyzed. It is shown that, under certain conditions, the MR-EDF energy can be interpreted as a functional of the one-body density matrix of the projected state with good particle number. Based on this observation, we propose a new approach, called Symmetry-Conserving EDF (SC-EDF), where the breaking and restoration of symmetry are accounted for simultaneously. We show, that such an approach is free from pathologies recently observed in MR-EDF and can be used with a large flexibility on the density dependence of the functional.

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Guillaume Hupin, Denis Lacroix, Michael Bender. 2011-05-30. Functional approach for pairing in finite systems: How to define restoration of broken symmetries in Energy Density Functional theory ?. https://doi.org/10.1088/1742-6596/321/1/012056

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