A Hybrid Organic‐Crystal‐Based Curved Waveguide Network for Producing, Splitting, and Transducing Multi‐Color Outputs

Hybrid optical components and circuits that deal with multiple signal generation and processing are quintessential for neural networking systems. Herein, the study reports the fabrication of one such component, a hybrid directional coupler (HDC) from blue emissive (4,4′‐bis(2,6‐di(1H‐pyrazol‐1‐yl)pyridin‐4‐yl)biphenyl) (BPP) and green emissive (E)‐1‐(((5‐bromopyridin‐2‐yl)imino)methyl)naphthalen‐2‐ol (BPyIN) pseudo‐plastic molecular crystals. Initially, a BPyIN microcrystal optical waveguide (OW1) is shaped into a strained waveguide with five bends using an atomic force microscopy cantilever‐tip aided mechanophotonics approach. Later, a singly bent BPyIN waveguide (OW2) is integrated into one of the bends at the coupling region on a strained waveguide to produce a 2 × 2 monolithic directional coupler (DC). Later, this 2 × 2 DC is extended to a HDC by integrating a blue emissive BPP waveguide (OW3) at another bend on the deformed waveguide. The fabricated HDC can effectively split the incident light into three parts with different split ratios and deliver multi‐color outputs depending on the port receiving the input signal. The spontaneous generation and processing of various signals produced in the circuit helps in understanding the functioning of complex optical neural networks. The demonstration of such innovative optical components manifests their utility for diverse applications in neural networking and quantum computing systems. Flexible organic crystal waveguides are ideal for creating innovative hierarchical optical circuits. Here, the study presents the fabrication of a hybrid directional coupler using electronically different two pseudo‐plastic organic crystals, serving as a key component for an artificial optical neural network system.