SCES Webinar Series
Correlation-driven electronic topology: The Weyl-Kondo semimetal Ce3Bi4Pd3
(Vienna University of Technology)
The ready tunability of strongly correlated electron systems by external parameters—rooted in low and competing energy scales—has enabled us to map out their phase diagrams, thereby identifying and classifying novel quantum phases, and elucidating the underlying physics . The nature of such phase diagrams in the presence of nontrivial electronic topology represents a new frontier. After a general discussion of this background I will focus on the heavy fermion material Ce3Bi4Pd3 , a semimetallic cousin of the well-known Kondo insulator Ce3Bi4Pt3. The strong spin-orbit coupling of the constituting elements together with the noncentrosymmetric and nonsymmorphic structure make this material a promising candidate for a certain type of nontrivial band topology. Indeed, our electrical transport and thermodynamic measurements evidence a highly unusual state—that of a Weyl semimetal with extreme topological response [2,3]. I will discuss how it can be understood as resulting from effects of strong correlations, leading to the notion of a Weyl-Kondo semimetal [2-5]. I will furthermore show how this new state of matter transforms under magnetic field tuning , and close by highlighting the potential of such tuning studies for future discovery.
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