Cooper pair sizes in 11Li and in superfluid nuclei: a puzzle?

TL;DR

This paper investigates how pairing forces affect the size of neutron Cooper pairs in exotic nuclei like 11Li, revealing unique behavior compared to stable superfluid nuclei.

Contribution

It highlights the significant influence of pairing interactions on Cooper pair sizes in 11Li, contrasting with stable nuclei where this effect is minimal.

Findings

Pairing force strongly affects Cooper pair size in 11Li.

In stable superfluid nuclei, pairing has little impact on pair size.

11Li exhibits unique pairing behavior compared to heavier nuclei.

Abstract

We point out a strong influence of the pairing force on the size of the two neutron Cooper pair in $^{11}$Li, and to a lesser extent also in $^6$He. It seems that these are quite unique situations, since Cooper pair sizes of stable superfluid nuclei are very little influenced by the intensity of pairing, as recently reported. We explore the difference between $^{11}$Li and heavier superfulid nuclei, and discuss reasons for the exceptional situation in $^{11}$Li.