Scientists uncover an extraordinary contest between charge density wave formation and superconductivity

In a groundbreaking study published in Nature Communications and recommended as a featured article, a research team led by Prof. CHEN Xianhui from the University of Science and Technology of China of the Chinese Academy of Sciences has discovered an unusual competition between charge density wave (CDW) and superconductivity in CsV3Sb5, a layered kagome metal.

The unusual competition between these two electronic states is a key aspect of CsV3Sb5's unique phase diagram. This competition is significant for the study of this material, as it sheds light on the complex CDW mechanism in CsV3Sb5.

Traditional superconductivity and CDW are two different electronic states that originate from electron-phonon coupling and Fermi instability, respectively. In the conventional coexistence image of CDW and superconductor, entering the CDW state opens an energy gap, resulting in the loss of density of states. However, in CsV3Sb5, the competition between these two states presents a more intricate picture.

When the pressure reaches 2 GPa, the CDW is completely compressed, and the superconducting critical transition temperature (Tc) can reach up to 8 K (three times of that at normal pressure), which is also the highest Tc reported for materials with cage structure. This anomalous double dome superconducting phase diagram may be caused by the transition from commensurate CDW state to nearly commensurate CDW state.

The study's findings offer experimental clues for understanding the unconventional CDW mechanism in CsV3Sb5. With the suppression of the CDW state, the Tc will show a single dome-like behavior. The results show that the superconducting state and CDW state of CsV3Sb5 are very sensitive to pressure, showing abundant pressure phase diagrams.

The research group led by Shiyan Li at the Shanghai Institute of Microsystem and Information Technology further explored this unusual competition between charge density wave enhancement and superconductivity in the kagome metal CsV3Sb5 using high-pressure studies and determined its phase diagram under high pressure.

The study's results provide valuable insights into the CDW mechanism in CsV3Sb5, which is a focus of interest due to the unusual competition with superconductivity. The study's findings could potentially lead to a better understanding of the coexistence and competition between superconductivity and CDW in CsV3Sb5.

CsV3Sb5 has a CDW transition temperature of 94 K, and its superconducting critical transition temperature (Tc) behaves as a double dome with the increase of pressure. This unusual competition between superconductivity and CDW is a key aspect of the material's electronic states and unique phase diagram. The study sheds light on the CDW mechanism in CsV3Sb5, which is a complex electronic state that is a focus of interest in the field.

In conclusion, the study's findings offer a significant step forward in understanding the unusual competition between superconductivity and CDW in CsV3Sb5, a layered kagome metal. The results could potentially contribute to a better understanding of the CDW phenomenon in CsV3Sb5 and other similar materials.

Scientists uncover an extraordinary contest between charge density wave formation and superconductivity