Wavelength conversion, time demultiplexing and multicasting based on cross-phase modulation and four-wave mixing in dispersion-flattened highly nonlinear photonic crystal fiber

Abstract

We propose the use of cross-phase modulation (XPM) and four-wave mixing (FWM) in dispersion-flattened highly nonlinear photonic crystal fibers (HNL-PCFs) to implement the functionalities of wavelength conversion, simultaneous time demultiplexing and wavelength multicasting in optical time-division multiplexing (OTDM) systems. The experiments on wavelength conversion at 80 Gbit s−1and OTDM demultiplexing from 80 to 10 Gbit s−1 with wavelength multicasting of two channels are successfully demonstrated to validate the proposed scheme, which are carried out by using two segments of dispersion-flattened HNL-PCFs with lengths of 100 and 50 m, respectively. Moreover, the bit error rate (BER) performance is also measured. The results show that our designed system can achieve a power penalty of less than 4.6 dB for two multicasting channels with a 24 nm wavelength span at the BER of 10−9 when compared with the 10 Gbit/s back-to-back measurement. The proposed system is transparent to bit rate since only an ultrafast third-order nonlinear effect is used. The resulting configuration is compact, robust and reliable, benefiting from the use of dispersion-flattened HNL-PCFs with short lengths. This also makes the proposed system more flexible in the operational wavelengths than those based on dispersion-shifted fibers and traditional highly nonlinear fibers.

Demonstration of 100 Gbit/s optical time‐division demultiplexing with 1‐to‐4 wavelength multicasting using the cascaded four‐wave mixing in photonic crystal fiber with a single control light source

“…It is clear that a conventional FWM interaction process between the control pulse and OTDM‐signal lights results in the generation of the first‐order FWM components at and , respectively. This in turn limits the number of wavelength multicasting channels to be equal to 2 after OTDM demultiplexing as reported in . To improve the wavelength‐multicasting capability without increasing the demultiplexer complexity, we present a new design for the PCF‐based OTDM demultiplexer using the cascaded FWM process.…”

“…With the increasing demand on video applications, a multicasting function is highly desirable for optical communication networks . The wavelength multicasting of an OTDM signal followed by the OTDM demultiplexing was reported in , but it used two HNLFs in multicasting and demultiplexing blocks, respectively.…”

“…For cost‐effective video distributions, it is advantageous to use an OTDM demultiplexer that also performs wavelength multicasting simultaneously. We have recently demonstrated the use of XPM and FWM in two PCFs for 80 Gbit/s wavelength conversion and 80 Gbit/s‐to‐10 Gbit/s OTDM demultiplexing with wavelength multicasting of two channels , respectively. In the resulting OTDM demultiplexer, a FWM interaction process between the control pulse and OTDM‐signal lights results in the generation of the first‐order FWM components at two distinct wavelengths of λ FWM1 and λ FWM2 , and therefore, could not be used to support wavelength multicasting applications if the required number of multicasting channels is larger than 2.…”

Design of optical time-division multiplexed systems using the cascaded four-wave mixing in a highly nonlinear photonic crystal fiber for simultaneous time demultiplexing and wavelength multicasting

“…Since optical time demultiplexing is one of key functions to build OTDM systems, there has been intensive research on the implementation of OTDM demultiplexers using optical nonlinearities [2][3][4][5][6][7][8][9][10]. For example, such demultiplexers can utilize cross-phase modulation (XPM) and four-wave mixing (FWM) in semiconductor optical amplifier (SOA) [8,9] and a variety of optical fibers [3][4][5][6][7][10][11][12][13][14][15][16][17], respectively. However, the operation speed of SOA-based demultiplexers can be ultimately limited by the relatively long gain recovery time in SOAs, and the amplified spontaneous emission noise of a SOA can also cause the degradation of the demultiplexed data signal.…”

All-optical NRZ-to-RZ format conversion at 10 Gbit/s with 1-to-4 wavelength multicasting exploiting cross-phase modulation & four-wave-mixing in single dispersion-flattened highly nonlinear photonic crystal fiber

“…This causes a chirp in the co-propagating NRZ data light via XPM and generates the sidebands on two sides of the NRZ data light. The leading edges of the NRZ data light are red-shifted, whereas the trailing edges are blue-shifted [21]. Consequently, the significant spectrum broadening of a NRZ signal light is observed at the output of a DF-HNL-PCF.…”