Theory of Diamagnetism in the Pseudogap Phase: Implications from the Self energy of Angle Resolved Photoemission

TL;DR

This paper uses ARPES-derived self energy to analyze orbital diamagnetism in underdoped cuprates, showing large diamagnetism consistent with a d-wave pseudogap across various theories.

Contribution

It demonstrates how the fermionic self energy from ARPES data can predict orbital diamagnetism in the pseudogap phase, independent of microscopic details.

Findings

Diamagnetism is large in the pseudogap phase.

Self energy consistent with ARPES data explains diamagnetism.

Compatibility with f-sum rules is established.

Abstract

In this paper we apply the emerging- consensus understanding of the fermionic self energy deduced from angle resolved photoemisssion spectroscopy (ARPES) experiments to deduce the implications for orbital diamagnetism in the underdoped cuprates. Many theories using many different starting points have arrived at a broadened BCS-like form for the normal state self energy associated with a d-wave excitation gap, as is compatible with ARPES data. Establishing compatibility with the f-sum rules, we show how this self energy, along with the constraint that there is no Meissner effect in the normal phase are sufficient to deduce the orbital susceptibility. We conclude, moreover, that diamagnetism is large for a d-wave pseudogap. Our results should apply rather widely to many theories of the pseudogap, independent of the microscopic details.