From Fermi Arcs to the Nodal Metal: Scaling of the Pseudogap with Doping and Temperature

TL;DR

This study reveals that the pseudogap phase in cuprates depends on the ratio T/T*, with Fermi arcs collapsing linearly as temperature decreases, indicating a nodal liquid state at zero temperature.

Contribution

It demonstrates that the anisotropy of the pseudogap and Fermi arcs depend solely on T/T*, providing new insight into the pseudogap's nature and its evolution with doping and temperature.

Findings

Fermi arcs depend only on T/T* ratio

Arcs collapse linearly with decreasing T

Zero-temperature pseudogap state is a nodal liquid

Abstract

The pseudogap phase in the cuprates is a most unusual state of matter: it is a metal, but its Fermi surface is broken up into disconnected segments known as Fermi arcs. Using angle resolved photoemission spectroscopy, we show that the anisotropy of the pseudogap in momentum space and the resulting arcs depend only on the ratio T/T*(x), where T*(x) is the temperature below which the pseudogap first develops at a given hole doping x. In particular, the arcs collapse linearly with T/T* and extrapolate to zero extent as T goes to 0. This suggests that the T = 0 pseudogap state is a nodal liquid, a strange metallic state whose gapless excitations are located only at points in momentum space, just as in a d-wave superconductor.