All-optical regenerator of multi-channel signals

Abstract

One of the main reasons why nonlinear-optical signal processing (regeneration, logic, etc.) has not yet become a practical alternative to electronic processing is that the all-optical elements with nonlinear input–output relationship have remained inherently single-channel devices (just like their electronic counterparts) and, hence, cannot fully utilise the parallel processing potential of optical fibres and amplifiers. The nonlinear input–output transfer function requires strong optical nonlinearity, e.g. self-phase modulation, which, for fundamental reasons, is always accompanied by cross-phase modulation and four-wave mixing. In processing multiple wavelength-division-multiplexing channels, large cross-phase modulation and four-wave mixing crosstalks among the channels destroy signal quality. Here we describe a solution to this problem: an optical signal processor employing a group-delay-managed nonlinear medium where strong self-phase modulation is achieved without such nonlinear crosstalk. We demonstrate, for the first time to our knowledge, simultaneous all-optical regeneration of up to 16 wavelength-division-multiplexing channels by one device. This multi-channel concept can be extended to other nonlinear-optical processing schemes.

Long-haul optical transmission link using low-noise phase-sensitive amplifiers

“…In ref. 26 , it was shown that two-mode PSAs potentially can be combined with multi-channel amplitude regenerators for multi-channel regeneration of advanced modulation formats. For details on the requirements regarding the tracking and alignment of polarization in PSA links see ref.…”

Scalable WDM phase regeneration in a single phase-sensitive amplifier through optical time lenses

“…Recent reports have shown optical amplitude regeneration of up to 12-channel WDM signals based on the Mamyshev scheme using a group-delay-managed nonlinear medium 3 . Very recently, the same group has extended their previous work, reporting amplitude regeneration of 16 channels with 100-GHz spacing 18 . However, WDM regeneration based on the Mamyshev scheme requires pre-fabrication of a set of fixed group delays, and is currently only effective for on–off-keying (OOK) signals.…”

RF and microwave photonic high bandwidth signal processing based on Kerr micro-comb sources

“…Nonlinear optics for all-optical signal processing has proven to be extremely powerful, particularly when implemented in photonic integrated circuits based on highly nonlinear materials such as silicon [1][2][3]. All optical signal processing functions include all-optical logic [4], demultiplexing from 160Gb/s [5] to over 1Tb/s [6], optical performance monitoring via slow light [7,8], all-optical regeneration [9,10], and others [11][12][13][14][15][16].…”