The topological properties of an object, associated with an integer called the topological
invariant, are global features that cannot change continuously but only through abrupt …

Topological photonics is a rapidly emerging field of research in which geometrical and
topological ideas are exploited to design and control the behavior of light. Drawing …

Topological systems are inherently robust to disorder and continuous perturbations,
resulting in dissipation-free edge transport of electrons in quantum solids, or reflectionless …

Photonic topological insulators enable topological boundary modes that are resilient to
defects and disorder, irrespective of manufacturing precision. This property is known as …

The Berry phase provides a modern formulation of electric polarization in crystals. We
extend this concept to higher electric multipole moments and determine the necessary …

Localized or propagating Majorana boundary modes are the key feature of topological
superconductors. They are rare in naturally occurring compounds, but the tailored …

Resonant cavities are essential building blocks governing many wave-based phenomena,
but their geometry and reciprocity fundamentally limit the integration of optical devices. We …

We experimentally demonstrate topological edge states arising from the valley-Hall effect in
two-dimensional honeycomb photonic lattices with broken inversion symmetry. We break the …

Topological insulators are crystalline solids with supposedly very special properties. If
stumbling upon such a crystal, which is possible because topological insulators are known …

Topological photonics has emerged as a promising field in photonics that is able to shape
the science and technology of light. As a significant degree of freedom, valley is introduced …