High-Speed Spiking and Bursting Oscillations in a Long-Delayed Broadband Optoelectronic Oscillator

We investigate the generation of high-speed spiking and bursting signals in a long time-delayed broadband optoelectronic oscillator (OEO). The OEO is configured in a delayed feedback loop employing a long optical fiber delay line and other elements including a tunable laser, a phase modulator (PM) and a linearly chirped fiber Bragg grating (LCFBG), a photodetector, and an electrical amplifier. The joint operation of the PM and the LCFBG forms an ultrawideband microwave photonic filter (MFP). Taking advantage of the multiple time scales arising from the MPF and the long optical fiber delay line, we are able to generate sub-nanosecond neuron-like spiking and bursting signals that emulate the response found to be the primary mode of electrical firing in biological neurons. Since our OEO can operate at a much higher speed and can be controlled using both time-delayed feedback employing low-loss optical fiber and electrical/optical injection locking techniques, it has interest in emerging photonics applications such as neuromorphic information processing and reservoir computing tasks.