Superconductivity and normal-state properties of kagome metal RbV3Sb5 single crystals

TL;DR

This paper reports the discovery of superconductivity in RbV3Sb5 single crystals with a kagome lattice, along with detailed normal-state properties including charge ordering and Dirac band features.

Contribution

It provides the first detailed characterization of superconductivity and normal-state anomalies in RbV3Sb5, highlighting charge order and Dirac band features in a kagome metal.

Findings

Superconducting transition at Tc ~ 0.92 K.

Anomalies at T* ~ 102-103 K indicating charge ordering.

Presence of small Fermi surfaces with Dirac bands.

Abstract

We report the discovery of superconductivity and detailed normal-state physical properties of RbV3Sb5 single crystals with V kagome lattice. RbV3Sb5 single crystals show a superconducting transition at Tc ~ 0.92 K. Meanwhile, resistivity, magnetization and heat capacity measurements indicate that it exhibits anomalies of properties at T* ~ 102 - 103 K, possibly related to the formation of charge ordering state. When T is lower than T*, the Hall coefficient RH undergoes a drastic change and sign reversal from negative to positive, which can be partially explained by the enhanced mobility of hole-type carriers. In addition, the results of quantum oscillations show that there are some very small Fermi surfaces with low effective mass, consistent with the existence of multiple highly dispersive Dirac band near the Fermi energy level.