We report that equidistant 1D arrays of thin-film lithium niobate nano-waveguides generically support topological edge states. Unlike conventional coupled-waveguide topological systems, the topological properties of these arrays are dictated by the interplay between intra- and inter-modal couplings of two families of guided modes with different parities. Exploiting two modes within the same waveguide to design a topological invariant allows us to decrease the system size by a factor of two and substantially simplify the structure. We present two example geometries where topological edge states of different types (based on either quasi-TE or quasi-TM modes) can be observed within a wide range of wavelengths and array spacings.
|Number of pages||4|
|Publication status||Published - 3 Apr 2023|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics