Remote synchronization in multi-layer semiconductor laser networks mediated by uncorrelated relay layer

In remote synchronization (RS) of multilayer networks, distant layers without direct connections can achieve isochronous synchronization through signal propagation mediated by relay layers. In previously observed cases of RS between two layers, the intermediate layer itself does not synchronize with them but typically exhibits a high degree of correlation. In this work, we report on a systematic investigation of RS in multilayer semiconductor laser (SL) networks mediated by uncorrelated relay layer, where dynamics of synchronized noncontiguous layers are uncorrelated with the intermediate part. We elucidate that the inter and intra layer coupling play a crucial role in this phenomenon, and it can be efficiently facilitated with the regulation of critical parameters of SLs and network topology. Finally, image encryption and decryption are achieved between the synchronized remote layers, while the relay layer, due to its uncorrelated characteristics, carries no extractable information. The relevant achievements break the inherent notion in traditional research that there should be some form of visible information in the communication paths between nodes exchanging information. Our results suggest potential applications in the field of secure communication.