Spin magnetization of small metallic grains

TL;DR

This paper investigates the spin magnetization of small metallic grains, demonstrating that interactions in different channels can be separated, enabling the determination of pairing correlations and interaction signs.

Contribution

It shows that spin and Cooper channel interactions in small metallic grains can be independently analyzed to identify pairing correlations and interaction signs.

Findings

Interactions in spin and Cooper channels are separable in small grains.

The existence of pairing correlations can be confirmed.

The sign of the Cooper channel interaction can be determined.

Abstract

Small metallic grains which satisfy the conditions of the universal Hamiltonian are considered. It is shown that for such grains the effects of the interactions in the spin channel and in the Cooper channel on their spin magnetization are well separated, thus allowing the determination of the interaction parameters within this model. In particular, the existence of pairing correlations in small grains and the sign of the interaction in the Cooper channel can be uniquely determined.