Topological photonic encoder based on the disclination states

Topological disclination states are highly localized and stable by means of introducing disclination, which provide a robust platform for realizing optical information transition. A photonic encoder, as a kind of optical information transition element, can record, transmit, and protect optical information. However, there is no effective methods to realize topological photonic encoders. In this work, we propose a method to realize topological photonic encoder through topological disclination states. After the introduction of a disclination in the honeycomb structure, four types of disclination states can be generated. To demonstrate the device to carry more information, nine disclination structures with different cylindrical radii are combined, and the disclination states can be denoted by digital signals 1-4 to prepare a topological photonic encoder. In addition, to improve the security of information transition, we build an encryption algorithm based on Morse code. This work provides a new idea for the construction of encoding devices and promotes the practical application of the topological disclination states.