论文标题
中子的茶介导的库珀配对：超越裸顶点近似
Pion-mediated Cooper pairing of neutrons: beyond the bare vertex approximation
论文作者
论文摘要
在一些量子中，许多粒子系统，费米子可以通过交换中间玻色子来形成库珀对。然后，这驱动了超导相变或超流体转变。理论上应使用适当的非扰动方法来研究此类转变。在这里，我们以中子超级流体过渡为例，并研究由中子物质低密度区域中的中性$π$ - 米斯氏介导的中子的库珀对。我们对中子含量$δ$，临界密度$ρ_{c} $以及临界温度$ t_c $进行了对中子含量$δ$的非扰动分析，并通过求解中子传播器的dyson-schwinger方程。我们首先在广泛使用的裸顶顶点近似下进行计算，然后结合最低阶顶顶点校正的贡献。即使在低密度下，这种顶点校正也不可以忽略不计，并且随着密度的增加，其重要性进一步增强。包括顶点校正后，在裸顶顶点近似下获得的密度温度平面上的过渡临界线会大大改变。这些结果表明，顶点校正起着重要作用，需要认真考虑。
In some quantum many particle systems, the fermions could form Cooper pairs by exchanging intermediate bosons. This then drives a superconducting phase transition or a superfluid transition. Such transitions should be theoretically investigated by using proper non-perturbative methods. Here we take the neutron superfluid transition as an example and study the Cooper pairing of neutrons mediated by neutral $π$-mesons in the low density region of a neutron matter. We perform a non-perturbative analysis of the neutron-meson coupling and compute the pairing gap $Δ$, the critical density $ρ_{c}$, and the critical temperature $T_c$ by solving the Dyson-Schwinger equation of the neutron propagator. We first carry out calculations under the widely used bare vertex approximation and then incorporate the contribution of the lowest-order vertex correction. This vertex correction is not negligible even at low densities and its importance is further enhanced as the density increases. The transition critical line on density-temperature plane obtained under the bare vertex approximation is substantially changed after including the vertex correction. These results indicate that the vertex corrections play a significant role and need to be seriously taken into account.
