7 citations · 10 across the 8 of their papers we have counts for
8 papers
Ideal Bands in Tight-Binding Models
Lexu Zhao, Yang Ge, Shinsei Ryu +1
A band is called ideal when its Dirichlet functional saturates the topological lower bound. We study ideal bands in finite-band tight-binding models with conventional two-dimension…
Higher-Form Anomalies on Lattices
Yitao Feng, Ryohei Kobayashi, Yu-An Chen +1
Higher-form symmetry in a tensor product Hilbert space is always emergent: the symmetry generators become genuinely topological only when the Gauss law is energetically enforced at…
Entanglement entropy in lattice models with quantum metric
Alexander Kruchkov, Shinsei Ryu
We revisit the connection between entanglement entropy and quantum metric in topological lattice systems, and provide an elegant and concise proof of this connection. In gapped two…
Higher Hall conductivity from a single wave function: Obstructions to symmetry-preserving gapped edge of (2+1)D topological order
Ryohei Kobayashi, Taige Wang, Tomohiro Soejima +2
A (2+1)D topological ordered phase with U(1) symmetry may or may not have a symmetric gapped edge state, even if both thermal and electric Hall conductivity are vanishing. It is re…
Higher bracket structure of density operators in Weyl fermion systems and topological insulators
Edwin Langmann, Shinsei Ryu, Ken Shiozaki
We study the algebraic structure of electron density operators in gapless Weyl fermion systems in spatial dimensions and in topological insulators (without any pro…
Spectral sum rules reflect topological and quantum-geometric invariants
Alexander Kruchkov, Shinsei Ryu
Topological invariants are fundamental characteristics reflecting global properties of quantum systems, yet their exploration has predominantly been limited to the static (DC) tran…
Noise probing of topological band gaps in dispersionless quantum states
Alexander Kruchkov, Shinsei Ryu
We uncover a useful connection between the integrated current noise and the topological band gap in dispersionless quantum states, $\int d ω[ \mathcal S^{\text{flat}}_{xx} +…
The Quantum Torus Chain
M. P. Qin, J. M. Leinaas, S. Ryu +3
We introduce a new set of one dimensional quantum lattice models which we refer to as The quantum torus chain. These models have discrete global symmetry, and projective on-site re…