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Updated: Jan 17, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Topological quantum phase transitions of topological Euler insulators
Ming-Da Dai1, Ai-Lei He2, Wei-Wei Luo1,3
1Center for Statistical and Theoretical Condensed Matter Physics, and Department of Physics, Zhejiang Normal University, Jinhua 321004, People's Republic of China.
Summary
This study introduces topological Euler insulators in a square lattice model, distinct from Chern insulators. Researchers observed a bulk-edge correspondence, enriching the understanding of Euler class topological phases.
Area of Science:
- Condensed Matter Physics
- Topological Matter Physics
Background:
- The Euler number is a topological invariant for two-dimensional topological band models with combined parity and time-reversal symmetry.
- It characterizes non-trivial interband topology for adjacent bands with real eigenstates.
- This differs from the Chern number, which describes single-band topology for complex eigenstates without time-reversal symmetry.
Purpose of the Study:
- To investigate a three-orbital square lattice model exhibiting topological Euler insulators.
- To analyze the bulk band structures, Wilson loop spectra, and Euler numbers.
- To explore the bulk-edge correspondence in topological Euler insulators.
Main Methods:
- Studied a three-orbital square lattice model.
- Analyzed bulk band structures and Wilson loop spectra.
- Calculated Euler numbers and constructed topological phase diagrams.
Main Results:
- Identified topological Euler insulators in the studied model.
- Observed a bulk-edge correspondence for these insulators, contrasting with Chern insulators.
- Presented topological phase diagrams based on Euler numbers for various parameters.
Conclusions:
- The findings enrich the understanding of Euler class topological phases.
- The study highlights a distinct bulk-edge correspondence for Euler insulators.
- Results may guide future material realizations of topological Euler insulators.
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