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Lifshitz Transition in Correlated Topological Semimetals
Byungkyun Kang1, Myoung-Hwan Kim2, Chul Hong Park3
1Department of Physics, The University of Texas at El Paso, El Paso, Texas, USA.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|March 24, 2026
Summary
Correlation effects in topological semimetals shift Dirac nodes away from the Fermi level. Temperature-dependent electronic structure changes, like Lifshitz transitions, are key to understanding these correlated topological materials.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Materials Science
Background:
- Topological quasiparticles are crucial for quantum devices.
- Correlated topological materials often have Dirac nodes shifted from the Fermi level, a phenomenon not fully understood.
Purpose of the Study:
- Investigate the electronic structure of YPtBi and GdPtBi.
- Explain the shift of quadratic band-touching points away from the chemical potential in these materials.
Main Methods:
- Utilized ab initio many-body perturbation GW theory.
- Employed dynamical mean-field theory.
- Analyzed the role of 4d or 4f electron correlations.
Main Results:
- Correlation effects in YPtBi and GdPtBi lead to hole carrier formation, shifting band-touching points.
- Weakly correlated Y-4d electrons in YPtBi form topological bands, with correlations causing hole pocket formation at low temperatures.
- Strongly correlated Gd-4f electrons in GdPtBi hybridize with topological bands, inducing hole bands and shifting the chemical potential closer to band-touching points.
Conclusions:
- Temperature-induced Lifshitz transitions can explain observed hole bands in topological semimetals.
- Integrating correlated fermions into topological frameworks reshapes Fermi surfaces without defect engineering.
- Experimental investigation of temperature-dependent electronic structure in topological semimetals is crucial.
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