High $T_c$ Superconductivity, Skyrmions and the Berry Phase

TL;DR

This paper explores how gauge fields, Berry phase, and skyrmions relate to high-temperature superconductivity, suggesting skyrmion pairing as a mechanism for superconductivity in doped antiferromagnets.

Contribution

It introduces a novel framework linking gauge fields, Berry phase, and skyrmions to high-$T_c$ superconductivity and antiferromagnetic correlations.

Findings

Antiferromagnetic spin fluctuations linked to gauge fields and Berry phase.

Skyrmion formation associated with charge carriers in the RVB state.

Superconductivity possibly arising from skyrmion-skyrmion bound states.

Abstract

It is here pointed out that the antiferromagnetic spin fluctuation may be associated with a gauge field which gives rise to the antiferromagnetic ground state chirality. This is associated with the chiral anomaly and Berry phase when we consider the two dimensional spin system on the surface of a 3D sphere with a monopole at the centre. This realizes the RVB state where spinons and holons can be understood as chargeless spins and spinless holes attached with magnetic flux. The attachment of the magnetic flux of the charge carrier suggest, that this may be viewed as a skyrmion. The interaction of a massless fermion representing a neutral spin with a gauge field along with the interaction of a spinless hole with the gauge field enhances the antiferromagnetic correlation along with the pseudogap at the underdoped region. As the doping increases the antiferromagnetic long range order disappears for the critical doping parameter $\delta_{sc}$. In this framework, the superconducting pairing may be viewed as caused by skyrmion-skyrmion bound states.