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Broadband wavelength conversion based on degenerate four-wave mixing is theoretically investigated in a hydrogenated amorphous silicon (a-Si:H) waveguide with silicon nitride inter-cladding layer (a-Si:HN). We have found that enhancement of the non-linear effect of a-Si:H waveguide nitride intermediate layer facilitates broadband wavelength conversion. Conversion bandwidth of 490 nm and conversion efficiency of 11.4 dB were achieved in a numerical simulation of a 4 mm-long a-Si:HN waveguide under 1.55 μm continuous wave pumping. This broadband continuous-wave wavelength converter has potential applications in photonic networks, a type of readily manufactured low-cost highly integrated optical circuits. [ABSTRACT FROM PUBLISHER]

We theoretically analyze the phase noise transfer issue between the pump and the wavelength-converted idler for a nondegenerate four-wave mixing (FWM) scheme, as well as study the vector theory in nonlinear semiconductor optical amplifiers (SOAs), in order to design a polarization-insensitive wavelength conversion system employing dual co-polarized pumps. A tunable sampled grating distributed Bragg reflector (SG-DBR) pump laser has been utilized to enable fast wavelength conversion in the sub-microsecond timescale. By using the detailed characterization of the SGDBR laser, we discuss the phase noise performance of the SGDBR laser. Finally, we present a reconfigurable SOA-based all-optical wavelength converter using the fast switching SGDBR tunable laser as one of the pump sources and experimentally study the wavelength conversion of the single polarization quadrature phase shift keying (QPSK) and polarization multiplexed (Pol-Mux) QPSK signals at 12.5-Gbaud. A wide tuning range (>10 nm) and less than 50 ns and 160 ns reconfiguration time have been achieved for the wavelength conversion system for QPSK and PM-QPSK signals, respectively. The performance under the switching environment after the required reconfiguration time is the same as the static case when the wavelengths are fixed. [ABSTRACT FROM AUTHOR]

We propose a slot-width switching (SWS) silicon–organic hybrid waveguide for broadband and efficient wavelength conversion. By switching the slot width of different lengths, the quasi-phase-matching can be obtained. Compared with width-modulated silicon-on-insulator (SOI) waveguide, the non-linear absorption can be ignored in slot waveguide which is filled with p-toluene sulphonate. Consequently, the conversion efficiency at a particular signal wavelength is improved, and the 3-dB conversion bandwidth is also extended. The numerical simulation results indicate that, for a continuous-wave pump at 1550 nm, a conversion bandwidth of 570 nm and a peak conversion efficiency of 11.32 dB can be realized in a 7.5-mm-long SWS waveguide, which is better than that of width-modulated SOI waveguide. [ABSTRACT FROM AUTHOR]

A new scheme for a flexible modulation and bit rate independent, polarization-insensitive optical wavelength converter (WC) based on four-wave mixing in a highly nonlinear fiber is demonstrated and characterized for different modulation formats and data rates. Its robustness is demonstrated in a data transmission experiment in which the WC is incorporated at the mid-point of a transmission line based on installed fiber. In addition, an optical feedback system designed to prevent slow polarization drift of the pumps, and consequently, to ensure the long-term stability of the system is implemented and characterized. The WC is tested with the feedback system in place enabling turn-key operation. [ABSTRACT FROM PUBLISHER]

The AlGaAs material platform has been intensively used to develop nonlinear photonic devices on-a-chip, thanks to its superior nonlinear optical properties. We propose a new AlGaAs waveguide geometry, called half-core etched, which represents a compromise between two previously studied geometries, namely the nanowire and strip-loaded waveguides, combining their best qualities. We performed tunable four-wave mixing (FWM) experiments in all three of these geometries in the telecommunications C-band (wavelengths around 1550 nm), with a pulsed pump beam and a continuous-wave (CW) signal beam. The maximum FWM peak efficiencies achieved in the nanowire, strip-loaded and half-core geometries were about − 5 dB , − 8 dB and − 9 dB , respectively. These values are among the highest reported in AlGaAs waveguides. The signal-to-idler conversion ranges were also remarkable: 161 nm for the strip-loaded and half-core waveguides and 152 nm for the nanowire. Based on our findings, we conclude that the half-core geometry is an alternative approach to the nanowire geometry, which has been earlier deemed the most efficient geometry, to perform wavelength conversion in the spectral region above the half-bandgap. Moreover, we show that the half-core geometry exhibits fewer issues associated with multiphoton absorption than the nanowire geometry. [ABSTRACT FROM AUTHOR]