The pseudogap: friend or foe of high Tc?

TL;DR

The paper reviews the ongoing debate about the pseudogap's role in high-temperature superconductors, highlighting its mysterious nature and significance in understanding strongly correlated electron systems.

Contribution

It summarizes discussions from a 2004 physics workshop on the pseudogap, emphasizing its unresolved questions and importance in high-Tc superconductivity research.

Findings

Pseudogap's physical origin remains unclear.

Debate on whether pseudogap is a distinct phase.

Significance of pseudogap in strongly correlated systems.

Abstract

Although nineteen years have passed since the discovery of high temperature superconductivity, there is still no consensus on its physical origin. This is in large part because of a lack of understanding of the state of matter out of which the superconductivity arises. In optimally and underdoped materials, this state exhibits a pseudogap at temperatures large compared to the superconducting transition temperature. Although discovered only three years after the pioneering work of Bednorz and Muller, the physical origin of this pseudogap behavior and whether it constitutes a distinct phase of matter is still shrouded in mystery. In the summer of 2004, a band of physicists gathered for five weeks at the Aspen Center for Physics to discuss the pseudogap. In this perspective, we would like to summarize some of the results presented there and discuss its importance in the context of strongly correlated electron systems.