We characterize non-Hermitian band structures by symmetry indicator topological invariants. Enabled crystalline inversion symmetry, these indicators allow us to short-cut the calculation of conventional In particular, we express three-dimensional winding number point-gapped systems, which is defined as an integral over whole Brillouin zone, in terms eigenvalues at high-symmetry momenta. Further...

A para-Kähler manifold can be defined as a pseudoRiemannian manifold (M, g) with a parallel skew-symmetric paracomplex structures K, i.e. a parallel field of skew-symmetric endomorphisms with K = Id or, equivalently, as a symplectic manifold (M, ω) with a bi-Lagrangian structure L, i.e. two complementary integrable Lagrangian distributions. A homogeneous manifold M = G/H of a semisimple Lie gro...

Non-Hermitian materials can not only exhibit exotic energy band structures but also an anomalous velocity induced by non-Hermitian Berry connection as predicted the semiclassical equations of motion for Bloch electrons. However, it is clear how modified dynamics modifies transport phenomena. Here, we theoretically demonstrate emergence oscillations driven either external dc or ac electric field...

Multidimensional lossless networks are of special interest for use as reference structures for multidimensional wave digital filters [1]-[3]. The starting point of the presented synthesis procedure for two-dimensional representatives of the networks mentioned is a scattering matrix description of the desired multiport. This given matrix is assumed to have those properties which have turned out ...

In this work we study a particular class of Lie bialgebras arising from Hermitian structures on Lie algebras such that the metric is ad-invariant. We will refer to them as Lie bialgebras of complex type. These give rise to Poisson Lie groups G whose corresponding duals G∗ are complex Lie groups. We also prove that a Hermitian structure on g with ad-invariant metric induces a structure of the sa...