Multiband one-dimensional electronic structure and spectroscopic signature of Tomonoga-Luttinger liquid behavior in K$_2$Cr$_3$As$_3$

TL;DR

This study uses ARPES to reveal Tomonoga-Luttinger liquid behavior in the quasi-one-dimensional superconductor K$_2$Cr$_3$As$_3$, showing linear dispersions and spectral suppression near the Fermi level indicative of non-Fermi liquid physics.

Contribution

First direct ARPES evidence of Tomonoga-Luttinger liquid signatures in K$_2$Cr$_3$As$_3$, highlighting its unconventional electronic properties and potential implications for superconductivity.

Findings

Linear dispersing bands with no significant renormalization

Spectral intensity suppression near Fermi level following a power law

Identification of Tomonoga-Luttinger liquid behavior in a superconductor

Abstract

We present Angle-Resolved Photoemission Spectroscopy measurements of the quasi-one dimensional superconductor K$_2$Cr$_3$As$_3$. We find that the Fermi surface contains two Fermi surface sheets, with linearly dispersing bands not displaying any significant band renormalizations. The one-dimensional band dispersions display a suppression of spectral intensity approaching the Fermi level according to a linear power law, over an energy range of ~200 meV. This is interpreted as a signature of Tomonoga-Luttinger liquid physics, which provides a new perspective on the possibly unconventional superconductivity in this family of compounds.