Quantized electric multipole insulators
Wladimir A. Benalcazar, B. Andrei Bernevig, Taylor L. Hughes
Summary
The paper generalizes the theory of electric polarization to higher electric multipole moments (quadrupole and octupole), showing these can be topologically quantized bulk observables in crystalline insulators. It introduces tight-binding models whose gapped edges are themselves lower-dimensional topological phases, producing protected, fractionally charged corner states. This work effectively launched the field of higher-order topological insulators.
Key findings
- Extends the modern theory of polarization to quantized quadrupole and octupole moments as topological invariants.
- Predicts gapped edges that host topologically protected mid-gap corner modes carrying fractional charge.
- Provides minimal lattice models later realized experimentally in photonic, acoustic, and electrical-circuit metamaterials.
Subjects & keywords
Cite this paper
Wladimir A. Benalcazar, B. Andrei Bernevig, & Taylor L. Hughes (2017). Quantized electric multipole insulators. Science. https://doi.org/10.1126/science.aah6442
@article{benalcazar2017quantized,
author = {Wladimir A. Benalcazar and B. Andrei Bernevig and Taylor L. Hughes},
title = {Quantized electric multipole insulators},
journal = {Science},
year = {2017},
doi = {10.1126/science.aah6442},
url = {https://doi.org/10.1126/science.aah6442}
}