The discovery of this phase transition not only showed a novel electronic nematicity, however provided fundamental experimental proof for additional understanding of the competitors in between superconductivity and CDW order in kagome systems. The findings likewise cast new light on the understanding of pair density wave (PDW) state in HTS.
Reference: “Charge-density-wave-driven electronic nematicity in a kagome superconductor” by Linpeng Nie, Kuanglv Sun, Wanru Ma, Dianwu Song, Lixuan Zheng, Zuowei Liang, Ping Wu, Fanghang Yu, Jian Li, Min Shan, Dan Zhao, Shunjiao Li, Baolei Kang, Zhimian Wu, Yanbing Zhou, Kai Liu, Ziji Xiang, Jianjun Ying, Zhenyu Wang, Tao Wu and Xianhui Chen, 9 February 2022, Nature.DOI: 10.1038/ s41586-022-04493-8.
Superconductivity in kagome state triggered by triple-Q CDW order. Credit: Image by NIE Linpengs group
In a recent short article released in Nature, a research group led by Prof. CHEN Xianhui, WU Tao and WANG Zhenyu from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences found the key proof for stage shift in a kagome superconductor CsV3Sb5. At a low temperature level, the group observed a transition from charge-density-wave (CDW) order to electronic nematicity which was first of all described by a three-state Potts model.
On the heels of the groups previous research study on triple-Q modulation of kagome superconductors and the unusual competition between superconductivity and charge-density-wave order, the team made another development in finding new states of electronic nematicities. They discovered that the triple-Q charge density wave state would evolve into a thermodynamically steady electron nematic stage prior to going into the superconducting state. They likewise managed to figure out the transition temperature level to be 35 Kelvin.
It is noteworthy that the electronic nematicity the group just recently discovered was disparate from the nematicity in high-temperature superconductors (HTS). The electronic nematicity in HTS is the Ising type with Z2 proportion; in contrast, the nematic stage found in CsV3Sb5 had Z3 symmetry.