Non-Abelian physics in light and sound

Y Yang, B Yang, G Ma, J Li, S Zhang, CT Chan - Science, 2024 - science.org
Non-Abelian phenomena arise when the sequence of operations on physical systems
influences their behaviors. By possessing internal degrees of freedom such as polarization …

General theory of momentum-space nonsymmorphic symmetry

C Zhang, ZY Chen, Z Zhang, YX Zhao - Physical Review Letters, 2023 - APS
As a fundamental concept of all crystals, space groups are partitioned into symmorphic
groups and nonsymmorphic groups. Each nonsymmorphic group contains glide reflections …

Synthetic non-Abelian gauge fields for non-Hermitian systems

Z Pang, BTT Wong, J Hu, Y Yang - Physical Review Letters, 2024 - APS
Non-Abelian gauge fields are versatile tools for synthesizing topological phenomena, but
have so far been mostly studied in Hermitian systems, where gauge flux has to be defined …

Synthetic gauge fields enable high-order topology on Brillouin real projective plane

J Hu, S Zhuang, Y Yang - arXiv preprint arXiv:2306.15477, 2023 - arxiv.org
The topology of the Brillouin zone, foundational in topological physics, is always assumed to
be a torus. We theoretically report the construction of Brillouin real projective plane …

Catalog of noninteracting tight-binding models with two energy bands in one dimension

E McCann - Physical Review B, 2023 - APS
We classify Hermitian tight-binding models describing noninteracting electrons on a one-
dimensional periodic lattice with two energy bands. To do this, we write a generalized Rice …

Higher-Order Topological Insulators via Momentum-Space Nonsymmorphic Symmetries

J Hu, S Zhuang, Y Yang - Physical Review Letters, 2024 - APS
We theoretically construct a higher-order topological insulator (HOTI) on a Brillouin real
projective plane enabled by momentum-space nonsymmorphic (k-NS) symmetries from …

Projective spacetime symmetry of spacetime crystals

Z Zhang, ZY Chen, YX Zhao - Communications Physics, 2023 - nature.com
Wigner's seminal work on the Poincaré group revealed one of the fundamental principles of
quantum theory: symmetry groups are projectively represented. The condensed-matter …

One-dimensional topological superconductor

M Tymczyszyn, E McCann - arXiv preprint arXiv:2404.07633, 2024 - arxiv.org
We describe the mean-field model of a one-dimensional topological superconductor with
two orbitals per unit cell. Time-reversal symmetry is absent, but a nonsymmorphic symmetry …