High Q Nanobeam cavity based on etchless lithium niobate integrated platform

Photonic bound states in the continuum (BICs) applied in the thin-film lithium-niobate-on-insulator (LNOI) has been exploited in multiple systems since it obviates the limitations of nano-fabrication. Here we firstly propose a nanobeam structure with BIC exhibiting a high Q factor of over 7000 with the length of only ~100 μm.