3 papers
cond-mat.mes-hall2025
Imaginary Time Formalism for Causal Nonlinear Response Functions
Sounak Sinha, Barry Bradlyn
It is well established that causal linear response functions can be found by computing the much simpler imaginary time-ordered Matsubara functions and performing an analytic contin…
cond-mat.str-el2025
Computing the Invariant in Two-Dimensional Strongly-Correlated Systems
Sounak Sinha, Derek Y. Pan, Barry Bradlyn
We show that the two-dimensional invariant for time-reversal invariant insulators can be formulated in terms of the boundary-condition dependence of the ground state…
cond-mat.mes-hall2025
Extrinsic Geometry and Gappable Edges in Rotationally Invariant Topological Phases
Sounak Sinha, Barry Bradlyn
Recent work on Abelian topological phases with rotational symmetry has raised the question of whether rotational symmetry can protect gapless propagating edge modes. Here we addres…