Wavelength conversion at 10 Gb/s by four-wave mixing over a 30-nm interval

We show that the use of a long semiconductor optical amplifier increases the error-free conversion interval of a four-wave mixing (FWM)-based wavelength converter. 30-nm wavelength down-conversion and 15-nm up-conversion have been obtained at 10 Gb/s. This result is a significant improvement over the previous best performance of a FWM-based wavelength converter and suggests that the full erbium-doped fiber amplifier bandwidth can be covered with FWM wavelength converters

30-nm wavelength conversion at 10 Gbit/s by four-wave mixing in a semiconductor optical amplifier

Four-wave mixing (FWM) in semiconductor optical amplifiers (SOAs) is currently the only available strictly transparent wavelength-conversion technique, which is not penalized by phase matching. The span of the conversion is limited primarily by conversion efficiency and signal-to-noise (SNR) issues, both of which are expected to improve with the use of longer SOAs. In this paper, we demonstrate significantly enhanced performance of long converters in a system experiment at 10 Gbit/s. The experiment shows for the first time, to our knowledge, that FWM wavelength down-conversions can span the full gain bandwidth of erbium-doped fiber amplifiers

Polarization Bistability in Tuned, External-Grating Diode Lasers

Spectral domains showing polarization-wavelength hysteresis regions up to 0.3 nm wide were observed when the emission frequency of a diode laser having a nearly polarization-independent confinement factor was tuned in a simple external cavity with grating. In these regions the laser emits in a stable single mode with either TE or TM polarization, depending on whether the region was entered from lower or higher wave-lengths. We explain the observed phenomenon on the basis of nonlinear gain saturation between TE and TM polarization. © 1995 IEE

Large Optical Bistability and Self Pulsations in Three Section DBR Laser Diode

A bistable operation with a hysteresis of 24 mA in the power-current curve of a three section DBR laser is reported. The laser threshold at increasing current is 51 mA while in the opposite direction the laser action is sustained down to 27 mA. The same effect was observed by monitoring the laser threshold through the Bragg and phase section currents. In a large part of the current range which corresponds to the bistable laser operation, strong self pulsations have been observed at frequencies between 1.5 GHz and 3.5 GHz with an amplitude of up to 31.4 dB. © 1994 IEE