报告题目：Long-range electron coherence in Kagome metals
报 告 人：Philip J. W. Moll (Max-Planck-Institute for Structure and Dynamics of Matter, Hamburg, Germany)
报告时间：2025年7月30日上午11:00
报告地点：物理楼W260
内容摘要：
Recently, materials based on the structural motif of the Kagome web have attracted significant attention for their tendency to host strongly coupled correlated phases. In particular, the centro-symmetric layered Kagome metals (K,Rb,Cs)V3Sb5 have entered the focus of experimental and theoretical research. They host a charge-density-wave type transition at elevated temperatures ~100K, followed by a superconducting transition at 3K. Yet there is another type of electronic order which thus far eludes exact microscopic identification. A series of experimental probes detects the onset of anomalous behavior around T’~30-40K, including thermal Hall, mSR, NMR, magnetic torque, Kerr rotation. The anomalous low-temperature state carries some characteristics of a chiral, nematic and time-reversal-symmetry breaking fluid (all of which are under most active debate currently). A series of recent experiments will be presented that suggest the first hint of an itinerant, long-range coherent state besides superconductivity. The results are based on mesoscopic coherence oscillations with a periodicity of the flux quantum, akin to the Aharonov-Bohm effect.
Key to this discovery is the need for many body physics in explaining the observed magnetoconductance oscillations, fueling the hypothesis of a novel type of long-range coherent collective state that contributes to the charge flow – a property thus far only observed in superconductivity. The collective nature is demonstrated by discontinuous global switching transitions between distinct quantum processes. Unraveling the microscopics of this enigmatic state has become a priority in the field.
[1] C. Guo et al., Nature 611, 461-466 (2022); [2] C. Guo et al., Nat. Phys. 20, 579 (2024); [3] C. Guo et al., 2504.13564v1 (2025)
报告人简介：
Philip Moll is the director of Max-Planck-Institute for Structure and Dynamics of Matter, Hamburg, Germany. He obtained PhD in 2012 at ETH Zurich, Switzerland, worked as a postdoc from 2012 till 2014 at ETH Zurich, Switzerland, and conducted research activities at UC Berkeley, USA, until 2016. He then moved to the MPI for Chemical Physics in Dresden as head of the Physics of Microstructured Quantum Matter research group. In 2018, he became Assistant Professor at the Institute of Materials of EPFL, Head of the Laboratory of Quantum Materials. He was promoted to Scientific member and director at the Max Planck Institute for Structure and Dynamics of Matter in 2021.
Philip Moll is the Winner of the Nicholas Kurti Science Prize (2018), the ABB Prize of the Swiss Physical Society (2014) and was selected as World Economic Forum Young Scientist 2020. In 2017, he received an ERC Starting Grant (2017) and a year later the Swiss National Science Foundation's Professorial Fellowship.
