Accidental bound state in the continuum in a chain of dielectric disks

M. S. Sidorenko, O. N. Sergaeva, Z. F. Sadrieva, C. Roques-Carmes, P. S. Muraev, D. N. Maksimov, and A. A. Bogdanov// 2021 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference OSA Technical Digest (Optica Publishing Group, 2021), paper jsi_2_4//

We experimentally analyze for the first time an off-Gamma BIC in a one-dimensional periodic chain of disks and demonstrate its transformation to a resonant state with the decrease of the chains length.