3 papers
physics.optics2026
Engineering symmetry-protected topological states in waveguide arrays
Lavi K. Upreti
The topological classification of a system depends on the discrete symmetries of its Hamiltonian. In Floquet photonic waveguide arrays, the abstract symmetries of the Altland--Zirn…
cond-mat.mes-hall2025
Topological non-Abelian gauge structures in Cayley-Schreier lattices
Zoltán Guba, Robert-Jan Slager, Lavi K. Upreti +1
Crystalline constructions known as Cayley-Schreier lattices have been suggested as a platform for realizing arbitrary gauge fields in synthetic crystals with real hopping amplitude…
cond-mat.mes-hall2020
Topological chiral interface states beyond insulators
Lavi K. Upreti, P. Delplace
We show how to engineer a chiral spectral flow of interface states in a gapless system. Although the bulk bands touch -- thus making the topological indices of the bands ill-define…