-
Article
Open AccessTopological classification for intersection singularities of exceptional surfaces in pseudo-Hermitian systems
Non-Hermitian systems are known for their intriguing topological properties, which underpin various exotic physical phenomena. Exceptional points, in particular, play a pivotal role in fine-tuning these system...
-
Article
Scalar topological photonic nested meta-crystals and skyrmion surface states in the light cone continuum
Topological photonics is rapidly expanding. However, discovering three-dimensional topological electromagnetic systems can be more challenging than electronic systems for two reasons. First, the vectorial natu...
-
Article
Non-Hermitian swallowtail catastrophe revealing transitions among diverse topological singularities
Exceptional points are a unique feature of non-Hermitian systems at which the eigenvalues and corresponding eigenstates of a Hamiltonian coalesce. Many intriguing physical phenomena arise from the topology of ...
-
Article
Open AccessSymmetry-protected topological exceptional chains in non-Hermitian crystals
In non-Hermitian systems, defective band degeneracies called exceptional points can form exceptional lines (ELs) in 3D momentum space in the absence of any symmetries. However, whether the presence of symmetri...
-
Article
Open AccessExperimental realization of chiral Landau levels in two-dimensional Dirac cone systems with inhomogeneous effective mass
Chiral zeroth Landau levels are topologically protected bulk states. In particle physics and condensed matter physics, the chiral zeroth Landau level plays a significant role in breaking chiral symmetry and gi...
-
Article
Open AccessTopological phononics arising from fluid-solid interactions
Nontrivial band topologies have been discovered in classical systems and hold great potential for device applications. Unlike photons, sound has fundamentally different dynamics and symmetries in fluids and so...
-
Article
Open AccessObservation of boundary induced chiral anomaly bulk states and their transport properties
The most useful property of topological materials is perhaps the robust transport of topological edge modes, whose existence depends on bulk topological invariants. This means that we need to make volumetric c...
-
Article
Classical non-Abelian braiding of acoustic modes
Non-Abelian braiding is regarded as an essential process for realizing quantum logic. Its realizations in quantum systems often rely on the dynamic winding of anyons, which can be challenging to obtain. Implem...
-
Article
Open AccessFour-band non-Abelian topological insulator and its experimental realization
Very recently, increasing attention has been focused on non-Abelian topological charges, e.g., the quaternion group Q8. Different from Abelian topological band insulators, these systems involve multiple entangled...
-
Article
Experimental observation of non-Abelian topological charges and edge states
In the last few decades, topological phase1–11 has emerged as a new classification of matter states beyond the Ginzburg–Landau symmetry-breaking paradigm. The underlying global invariant is usually well character...
-
Article
Open AccessIntrinsic in-plane nodal chain and generalized quaternion charge protected nodal link in photonics
Nodal lines are degeneracies formed by crossing bands in three-dimensional momentum space. Interestingly, these degenerate lines can chain together via touching points and manifest as nodal chains. These nodal...
-
Article
Open AccessMomentum space toroidal moment in a photonic metamaterial
Berry curvature, the counterpart of the magnetic field in the momentum space, plays a vital role in the transport of electrons in condensed matter physics. It also lays the foundation for the emerging field of...
-
Article
Open AccessHidden-symmetry-enforced nexus points of nodal lines in layer-stacked dielectric photonic crystals
It was recently demonstrated that the connectivities of bands emerging from zero frequency in dielectric photonic crystals are distinct from their electronic counterparts with the same space groups. We discove...
-
Article
Open AccessNon-Abelian gauge field optics
The concept of gauge field is a cornerstone of modern physics and the synthetic gauge field has emerged as a new way to manipulate particles in many disciplines. In optics, several schemes of Abelian synthetic...
-
Article
Near-perfect transmission through thick apertures by inserting connected ring resonators
We report the largely enhanced transmission of electromagnetic waves through periodic subwavelength thick apertures in an opaque plate by inserting connected ring resonators through the apertures at selected m...
-
Article
Residents’ environmental conservation behaviour in the mountain tourism destinations in China: Case studies of Jiuzhaigou and Mount Qingcheng
This study aimed at gaining an understanding of the formation of residents’ Environmental Conservation Behaviour (ECB) to promote sustainable tourism development in Chinese mountain areas. In particular, a the...
-
Article
Yang–Baxter equations and quantum entanglements
In this paper some results associated with a new type of Yang–Baxter equation (YBE) are reviewed. The braiding matrix of Kauffman–Lomonaco has been extended to the solution (called type-II) of Yang–Baxter equa...
-
Article
Open AccessTime Circular Birefringence in Time-Dependent Magnetoelectric Media
Light traveling in time-dependent media has many extraordinary properties which can be utilized to convert frequency, achieve temporal cloaking and simulate cosmological phenomena. In this paper, we focus on t...
