title: Improving performance of optical phase conjugation by splitting the nonlinear element.
abstract: We show that optical phase conjugation (OPC) based on third order nonlinear effects for mid-span spectral inversion (MSSI) can be improved by splitting the nonlinear element into two parts and adding an optical filter between them. This band-stop filter suppresses the cross-phase-modulation products that are generated around the pump, which, if not removed, will be shifted to fall around the output OPC signal band. Numerical simulations show that this method reduces the fundamental limitations introduced by OPC by 3 dB, which results in improvement of the maximum signal quality, Qmax, by 1 dB in a 10 × 80-km 4-QAM 224-Gb/s CO-OFDM system with MSSI.
authors.affiliation: Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Department of Electrical & Computer Systems Engineering, Monash University, Clayton, VIC 3800, Australia.
authors.forename: Monir
authors.initials: M
authors.lastname: Morshed
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Lowery
authors.forename: Liang B
authors.initials: LB
authors.lastname: Du
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D017711:Nonlinear Dynamics; D055096:Optical Devices; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013685:Telecommunications / Q000295:instrumentation*