Diamagnetism of real-space pairs above Tc in hole doped cuprates

TL;DR

This paper challenges the idea of Cooper pairing above Tc in hole-doped cuprates, proposing that the observed diamagnetism is due to real-space pairs behaving as bosons, not vortex liquid.

Contribution

It demonstrates that the nonlinear diamagnetism in cuprates is consistent with Landau diamagnetism of real-space bosonic pairs rather than Cooper pairs or vortex liquid.

Findings

Diamagnetism aligns with Landau diamagnetism of real-space pairs

Incompatibility of observed diamagnetism with vortex liquid model

Applicable to both less and highly anisotropic cuprates

Abstract

The nonlinear normal state diamagnetism reported by Lu Li et al. [Phys. Rev. B 81, 054510 (2010)] is shown to be incompatible with an acclaimed Cooper pairing and vortex liquid above the resistive critical temperature. Instead it is perfectly compatible with the normal state Landau diamagnetism of real-space composed bosons, which describes the nonlinear magnetization curves in less anisotropic cuprates La-Sr-Cu-O (LSCO) and Y-Ba-Cu-O (YBCO) as well as in strongly anisotropic bismuth-based cuprates in the whole range of available magnetic fields.