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Updated: Dec 22, 2025
09:00
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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A signature index for third order topological insulators
L B Drissi1,2,3, E H Saidi1,2
1LPHE, Modeling & Simulations, Faculty of Science, Mohammed V University, Rabat, Morocco.
Summary
Researchers developed a new index signature to characterize third-order topological phases in 3D systems. This method generalizes to N-dimensional systems, efficiently calculating topological invariants.
Area of Science:
- Condensed Matter Physics
- Topological Matter Physics
Background:
- Topological phases of matter exhibit unique properties protected by topology.
- Characterizing higher-order topological phases, especially in three dimensions, remains an active research area.
Purpose of the Study:
- To develop a novel index signature for characterizing third-order topological phases in three-dimensional (3D) systems.
- To generalize this characterization method to N-dimensional systems with open boundaries.
Main Methods:
- The proposed index is an alternating sum of monomial signatures of Higgs triplet values at 3D corners.
- The method is extended to N-dimensional systems, demonstrating efficient generalization of topological invariants.
Main Results:
- A new index signature for third-order topological phases in 3D systems is successfully developed.
- The method is shown to be applicable to N-dimensional systems, including second-order topological insulators.
- Known results for lower-dimensional systems are recovered, and an interpretation in Higgs space parameters is provided.
Conclusions:
- The developed index provides a robust method for characterizing higher-order topological phases across various dimensions.
- This work offers a unified framework for understanding topological invariants in systems with open boundaries.
Keywords:
Benalcazar--Bernevig--Hughes lattice modelsHiggs spaceindex theoremsecond and third order topological insulatorsMore Related Videos
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