Wideband JK flip-flop based on cascaded silica waveguide Mach-Zehender interferometers

Direct optical logic gates represent crucial components for optical computing systems. We present an optical JK flip-flop with cascaded Mach-Zehnder interferometers (MZIs). The JK flip-flop functionality is implemented by leveraging MZI modulation and mode filtering. Operating at 1550 nm, the output ports exhibit extinction ratios exceeding 17.69 dB. Notably, the wideband operation across the wavelength range of 1500-1620 nm maintains extinction ratios greater than 13.46 dB. This simple but reliable structure can be applied to other planar lightwave circuit platforms.