792 citations · 6.7k across the 69 of their papers we have counts for
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Symmetry indicators and anomalous surface states of topological crystalline insulators
Eslam Khalaf, Hoi Chun Po, Ashvin Vishwanath +1
The rich variety of crystalline symmetries in solids leads to a plethora of topological crystalline insulators (TCIs) featuring distinct physical properties, which are conventional…
Fragile Topology and Wannier Obstructions
Hoi Chun Po, Haruki Watanabe, Ashvin Vishwanath
Topological phases, such as Chern insulators, are defined in terms of additive indices that are stable against the addition of trivial degrees of freedom. Such topology presents an…
Structure and Topology of Band Structures in the 1651 Magnetic Space Groups
Haruki Watanabe, Hoi Chun Po, Ashvin Vishwanath
The properties of electrons in magnetically ordered crystals are of interest both from the viewpoint of realizing novel topological phases, such as magnetic Weyl semimetals, and fr…
Interacting invariants for Floquet phases of fermions in two dimensions
Lukasz Fidkowski, Hoi Chun Po, Andrew C. Potter +1
We construct a many-body quantized invariant that sharply distinguishes among two dimensional non-equilibrium driven phases of interacting fermions. This is an interacting generali…
Lattice Homotopy Constraints on Phases of Quantum Magnets
Hoi Chun Po, Haruki Watanabe, Chao-Ming Jian +1
The Lieb-Schultz-Mattis (LSM) theorem and its extensions forbid trivial phases from arising in certain quantum magnets. Constraining infrared behavior with the ultraviolet data enc…
Floquet topological phases protected by time glide symmetry
Takahiro Morimoto, Hoi Chun Po, Ashvin Vishwanath
We study Floquet topological phases in periodically driven systems that are protected by "time glide symmetry", a combination of reflection and half time period translation. Time g…
Symmetry-based Indicators of Band Topology in the 230 Space Groups
Hoi Chun Po, Ashvin Vishwanath, Haruki Watanabe
The interplay between symmetry and topology leads to a rich variety of electronic topological phases, protecting states such as the topological insulators and Dirac semimetals. Pre…
Radical chiral Floquet phases in a periodically driven Kitaev model and beyond
Hoi Chun Po, Lukasz Fidkowski, Ashvin Vishwanath +1
Time periodic driving serves not only as a convenient way to engineer effective Hamiltonians, but also as a means to produce intrinsically dynamical phases that do not exist in the…