Control of cooperative electronic states in Kagome metals
When the music changes, so does the dance: Controlling cooperative electronic states in kagome metals. This is the title of the press release from the MPI for the Structure and Dynamics of Matter (MPSD) on a paper published in Nature in February 2024, which was led by scientists from the Max Planck Institute in Hamburg. The authors also include Maia Vergniory and Claudia Felser (Department TQC) of the MPI CPfS.
The publication is the result of the ongoing collaboration on Kagome superconductors of the composition AV3Sb5 between the group of Philip Moll at the MPI for the Structure and Dynamics of Matter and the TQC department at the MPI CPfS. The team has been researching these materials, which are the subject of heated debate among experts, for over two years. This is because controversial experimental results have been observed on them. Due to their structural composition and the associated magnetic frustrations, the kagome materials react very strongly even to seemingly minor disturbances.
Using a novel stress-free measurement method, the researchers were able to identify the inherent ground state of the compound CsV3Sb5 without disturbances. And thus show that the contradictory observations at first glance are a feature of this class of compounds and not a mistake. This property is a direct consequence of the unconventional ground state of CsV3Sb5, which has several intertwined electronic orders. Therefore, the system can be detached from its actual ground state by the slightest external perturbations such as strains or magnetic fields, leading to controversial experimental observations.
The above text is an excerpt from the full [press release] of the Max Planck Institute for the Structure and Dynamics of Matter.