Berry bands and pseudo-spin of topological photonic phases
File(s)
Published version
Author(s)
Palmer, Samuel J
Giannini, Vincenzo
Type
Journal Article
Abstract
Realising photonic analogues of the robust, unidirectional edge states of
electronic topological insulators would improve our control of light on the
nanoscale and revolutionise the performance of photonic devices. Here we show
that new symmetry protected topological phases can be detected by reformulating
energy eigenproblems as Berry curvature eigenproblems. The "Berry bands" span
the same eigenspace as the original valence energy bands, but separate into
pseudo-spinful and pseudo-spinless subspaces in
$\mathrm{C}_2\mathcal{T}$-symmetric crystals. We demonstrate the method on the
well-known case of Wu & Hu [Phys. Rev. Lett. 114, 223901 (2015)] and a recently
discovered fragilely topological crystal, and show that both crystals belong to
the same $\mathrm{C}_2\mathcal{T}$-protected $\mathbb{Z}_2$ topological phase.
This work helps unite theory and numerics, and is useful in defining and
identifying new symmetry-protected phases in photonics and electronics.
electronic topological insulators would improve our control of light on the
nanoscale and revolutionise the performance of photonic devices. Here we show
that new symmetry protected topological phases can be detected by reformulating
energy eigenproblems as Berry curvature eigenproblems. The "Berry bands" span
the same eigenspace as the original valence energy bands, but separate into
pseudo-spinful and pseudo-spinless subspaces in
$\mathrm{C}_2\mathcal{T}$-symmetric crystals. We demonstrate the method on the
well-known case of Wu & Hu [Phys. Rev. Lett. 114, 223901 (2015)] and a recently
discovered fragilely topological crystal, and show that both crystals belong to
the same $\mathrm{C}_2\mathcal{T}$-protected $\mathbb{Z}_2$ topological phase.
This work helps unite theory and numerics, and is useful in defining and
identifying new symmetry-protected phases in photonics and electronics.
Date Issued
2021-05-01
Date Acceptance
2021-03-31
Citation
Physical Review Research, 2021, 3 (2)
ISSN
2643-1564
Publisher
American Physical Society
Journal / Book Title
Physical Review Research
Volume
3
Issue
2
Copyright Statement
© The Author(s) 2021. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
License URL
Identifier
http://arxiv.org/abs/2009.07033v2
Subjects
physics.optics
physics.optics
cond-mat.mes-hall
Notes
4 pages, 4 figures
Publication Status
Published
Article Number
ARTN L022013
Date Publish Online
2021-05-18