Simultaneous Phase Regeneration of MDM Signals Utilizing a Multimode Silicon Waveguide

Abstract

Mode-division multiplexing (MDM) is an effective technique to enlarge the transmission capacity. In order to extend the transmission distance and increase the transparency of the phase-encoded MDM communication system, all optical phase regeneration (PR) for MDM signals is much in demand. However, the PR of the MDM signals has been rarely reported. In this paper, the simultaneous PR of the MDM signals is proposed and theoretically demonstrated. The PR performance relies on the dispersion engineering of a multimode nonlinear waveguide, obtaining strong intramode phase sensitive amplifications (PSAs), where the involved pumps and the MDM signal component are carried on the same mode. On the other hand, the weak PSA/four wave mixing interaction is ensured among different modes, owing to the large phase mismatch or weak nonlinear coupling. Detailed characteristics are investigated to further optimize the PR performance. Results show an effective phase squeezing for the degraded 20 Gbit/s MDM differential phase-shift keying signals, and the error vector magnitudes of the regenerated signals on dual modes are improved from 10.7% and 11.5% to 4.9% and 3.7%, respectively.