572 citations · 887 across the 10 of their papers we have counts for
10 papers
Dynamical Poles in Non-Hermitian Impurity Scattering
Ao Yang, Kai Zhang, Chen Fang
In Hermitian impurity scattering, each isolated late-time exponential is the fingerprint of a bound state. We show that this correspondence breaks down in non-Hermitian bands. For…
Constructions and Applications of Irreducible Representations of Spin-Space Groups
Ziyin Song, A. Z. Yang, Yi Jiang +5
Spin-space groups (SSGs), including the traditional space groups (SGs) and magnetic space groups (MSGs) as subsets, describe the complete symmetries of magnetic materials with weak…
Enumeration of spin-space groups: Towards a complete description of symmetries of magnetic orders
Yi Jiang, Ziyin Song, Tiannian Zhu +5
Symmetries of three-dimensional periodic scalar fields are described by 230 space groups (SGs). Symmetries of three-dimensional periodic (pseudo-) vector fields, however, are descr…
Dynamical Degeneracy Splitting and Directional Invisibility in Non-Hermitian Systems
Kai Zhang, Chen Fang, Zhesen Yang
In this paper, we introduce the concept of dynamical degeneracy splitting to describe the anisotropic decay behaviors in non-Hermitian systems. We demonstrate that systems with dyn…
Non-Hermitian Topology and Exceptional-Point Geometries
Kun Ding, Chen Fang, Guancong Ma
Non-Hermitian theory is a theoretical framework that excels at describing open systems. It offers a powerful tool in the characterization of both the intrinsic degrees of freedom (…
Symmetry invariants and classes of quasiparticles in magnetically ordered systems having weak spin-orbit coupling
Jian Yang, Zheng-Xin Liu, Chen Fang
Symmetry invariants of a group specify the classes of quasiparticles, namely the classes of projective irreducible co-representations in systems having that symmetry. More symmetry…
A Hamiltonian Approach for Obtaining Irreducible Projective Representations and the Perturbation for Anti-unitary Symmetry Groups
Zhen-Yuan Yang, Jian Yang, Chen Fang +1
As is known, the irreducible projective representations (Reps) of anti-unitary groups contain three different situations, namely, the real, the complex and quaternion types with to…
Symmetry-protected Nodal Points and Nodal Lines in Magnetic Materials
Jian Yang, Chen Fang, Zheng-Xin Liu
Nodal-point and Nodal-line structures in the dispersion of electron energy bands are characterized by their high degeneracy in certain corners or lines in the Brillouin zone (BZ).…
Unlocking of time reversal, space-time inversion and rotation invariants in magnetic materials
Jian Yang, Zheng-Xin Liu, Chen Fang
Time reversal () and space inversion are symmetries of our universe in the low-energy limit. Fundamental theorems relate their corresponding quantum numbers to the spin for elem…
Real-space recipes for general topological crystalline states
Zhida Song, Chen Fang, Yang Qi
Topological crystalline states are short-range entangled states jointly protected by onsite and crystalline symmetries. While the non-interacting limit of these states, e.g., the t…