Chiral charge order in the superconductor 2H-TaS2

TL;DR

This paper reports the discovery of chiral charge order in the superconductor 2H-TaS2 using STM/S at very low temperatures, revealing complex charge modulations and superconducting properties.

Contribution

It demonstrates the presence of chiral charge order in 2H-TaS2 and characterizes its superconducting gap and charge density wave features.

Findings

Chiral charge order observed with clockwise and counterclockwise modulations

Superconducting gap centered around 0.28 meV

Superconductivity disappears at Tc = 1.75 K

Abstract

We find chiral charge order in the superconductor 2H-TaS2 using Scanning Tunneling Microscopy and Spectroscopy (STM/S) at 0.1 K. Topographic images show hexagonal atomic lattice and charge density wave (CDW) with clockwise and counterclockwise charge modulations. Tunneling spectroscopy reveals the superconducting density of states, disappearing at Tc = 1.75 K and showing a wide distribution of values of the superconducting gap, centered around \Delta=0.28 meV.