标题： 有限系统中的配对功能方法：如何在能量密度泛函理论中定义破缺对称性的恢复？ 显示英文标题

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

摘要： 多参考能量密度泛函（MR-EDF）方法（也称为组态混合或生成坐标方法），通常用于处理有限核中的配对并投影到粒子数，被重新分析。 显示在某些条件下，MR-EDF能量可以解释为具有良好粒子数的投影态的一体密度矩阵的泛函。 基于这一观察，我们提出一种新方法，称为对称性保持的EDF（SC-EDF），其中对称性的破缺和恢复同时得到考虑。 我们表明，这种方法可以避免最近在MR-EDF中观察到的病态，并且可以在泛函的密度依赖性上具有很大的灵活性。 显示英文摘要

摘要： 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.