Preprint Open Access
Scaffardi, Mirco; Muhammad N. Malik; Lazzeri Emma; Meloni Gianluca; Fresi Francesco; Potì Luca; Andriolli Nicola; Cerutti Isabella; Klitis Charalambos; Meriggi Laura; Zhang Ning; Sorel Marc; Bogoni Antonella
The orbital angular momentum (OAM) of light can be exploited as an additional switching domain together with more traditional switching domains as wavelength, space and time to implement multi-layer interconnection networks with high capacity, low power consumption and fast reconfiguration time. In this work we propose a two-layer optical interconnection network exploiting OAM and wavelength as switching domains. The key component of the interconnection network is the OAM-based switching element, here implemented on a silicon-on-insulator chip exploiting microrings. This implementation allows fast tuning (down to nanosecond range) and low power consumption (a few tens of mW per microring). We report the first implementation of an OAM-based 2x2 switch exploiting a dual-grating microring. The measurements are taken for OOK and 16QAM input signals modulated up to 35Gbaud. A bit error rate below the forward error correction threshold is demonstrated up to 20Gbaud for all the switching scenarios, with power penalty <1dB with respect to the back-to-back. A characterization of the integrated microring is carried out also in terms of beam divergence for different radii and emitted OAM orders. The characterization has brought to an empirical model which can aid the microring design in order to optimize the collimation of the OAM beams through the interconnection network.