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Phase-Space Approach for Topological Phase Transitions in Silicene
Maciej Kalka1, Piotr Pigoń1, Bartłomiej J Spisak1
1Faculty of Physics and Applied Computer Science, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland.
Entropy (Basel, Switzerland)
|August 28, 2025
Summary
Researchers explored topological phase transitions in silicene using a novel phase-space approach. They utilized Wigner-Rényi entropy and topological quantum numbers to detect these transitions under electric and magnetic fields.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Silicene, a 2D silicon allotrope, exhibits a tunable band gap influenced by spin-orbit coupling and external electric fields.
- Electric field modulation can induce transitions between topological insulator and bulk insulator states in silicene.
Purpose of the Study:
- To develop a phase-space approach for detecting topological phase transitions in silicene.
- To investigate silicene's topological phase transitions under combined parallel electric and magnetic fields.
- To employ topological quantum numbers derived from Wigner-Rényi entropy as an indicator for these transitions.
Main Methods:
- Utilized a reinterpreted Wigner distribution function to define a topological quantum number.
- Applied Wigner-Rényi entropy, including one-half, Shannon, and collision entropies, to quantify topological properties.
- Analyzed phase-space dynamics to identify transitions induced by electric and magnetic fields.
Main Results:
- Successfully developed a phase-space method to detect topological phase transitions in silicene.
- Demonstrated that the topological phase transition is dependent on the applied electric field strength in the presence of a magnetic field.
- Confirmed the validity of the topological quantum number derived from Wigner-Rényi entropy for characterizing these transitions.
Conclusions:
- The study presents a robust method for identifying topological phase transitions in silicene.
- The findings highlight the crucial role of electric and magnetic fields in controlling silicene's topological states.
- Wigner-Rényi entropy serves as an effective tool for characterizing topological quantum numbers and phase transitions in 2D materials.
Keywords:
Landau statesWigner distribution functionWigner–Rényi entropysilicenetopological phase transitiontopological quantum numberMore Related Videos
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