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Reversible layered/non-layered phase transition in a topological semimetal
Qingrong Liang1, Jiali Chen1, Zhaoyang Xie1
1Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Nature Communications
|July 21, 2026
Summary
Researchers achieved a reversible phase transition between layered and non-layered structures in PtBi2. This discovery enables new possibilities for exploring quantum states through phase engineering.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Chemistry
Background:
- Phase transitions are typically governed by symmetry breaking, as described by Landau's theory.
- Isocompositional transitions between layered and non-layered structures are challenging due to differences in surface energies and bonding.
- Discovering emergent quantum phases relies on understanding materials' structural transformations.
Purpose of the Study:
- To demonstrate a reversible phase transition between layered and non-layered structures in the semimetal PtBi2.
- To investigate the diverse structural and physical properties of these distinct phases.
- To establish a platform for phase engineering to explore topological and functional quantum states.
Main Methods:
- Experimental synthesis and characterization of PtBi2.
- Electrical measurements to observe resistance hysteresis loops.
- Theoretical calculations to support observed phenomena and topological properties.
Main Results:
- A reversible phase transition between layered and non-layered structures was achieved in PtBi2.
- Electrical measurements revealed reversible resistance hysteresis loops linked to the phase transition.
- Theoretical calculations confirmed structure-dependent topological invariants associated with the phase transition.
Conclusions:
- The demonstrated reversible phase transition in PtBi2 provides a novel mechanism for materials engineering.
- Intralayer splitting and interlayer reconstructions drive the observed resistance hysteresis.
- Layered/non-layered phase engineering offers a promising route for exploring novel quantum phenomena.
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