The breakdown of the conventional bulk-boundary correspondence due to non-Hermitian skin effect leads to the non-Bloch bulk-boundary correspondence in the generalized Brillouin zone. Inspired by the case of the equivalence between the non-reciprocal
hopping and imaginary gauge field, we propose a method to construct the topological equivalent models of the non-Hermitian dimerized lattices with the similarity transformations. The idea of the constructions is from that the imaginary magnetic flux vanishes under the open boundary condition and the period boundary spectra can be well approximated by open boundary spectra. As an illustration, we apply this approach to several representative non-Hermitian SSH models, efficiently obtaining topological invariants in analytic form defined in the conventional Bloch bands. The method gives an alternative way to study the topological properties of non-Hermitian system.
The new-found two-dimensional antiferromagnetic GdTe$_3$ is attractive owing to its highest carrier mobility among all known layered magnetic materials, as well as its potential application for novel magnetic twistronic and spintronic devices. Here,
we have used high-resolution angle-resolved photoemission spectroscopy to investigate its Fermi surface topology and low-lying electronic band structure. The Fermi surface is partially gapped by charge density wave below the transition temperature, the residual part reconstructs making GdTe$_3$ metallic. The high carrier mobility can be attributed to the sharp and nearly linear band dispersions near the Fermi energy. We find that the scattering rate of the linear band near the Fermi energy is almost linear within a wide energy range, indicating that GdTe$_3$ is a non-Fermi liquid metal. Our results in this paper provide a fundamental understanding of this layered Van der Waals antiferromagnetic materials to guide future studies on it.
