Wavelength conversion of complex modulation formats in a compact SiGe waveguide

We report a nonlinear signal processing system based on a SiGe waveguide suitable for high spectral efficiency data signals. Four-wave-mixing (FWM)-based wavelength conversion of 10-Gbaud 16-Quadrature amplitude modulated (QAM) and 64-QAM signals is demonstrated with less than -10-dB conversion efficiency (CE), 36-dB idler optical signal-to-noise ratio (OSNR), negligible bit error ratio (BER) penalty and a 3-dB conversion bandwidth exceeding 30nm. The SiGe device was CW-pumped and operated in a passive scheme without giving rise to any two-photon absorption (TPA) effects.

High peak-power picosecond pulse generation at 1.26 µm using a quantum-dot-based external-cavity mode-locked laser and tapered optical amplifier

In this paper, we present the generation of high peak-power picosecond optical pulses in the 1.26 μm spectral band from a repetition-rate-tunable quantum-dot external-cavity passively mode-locked laser (QD-ECMLL), amplified by a tapered quantum-dot semiconductor optical amplifier (QD-SOA). The laser emission wavelength was controlled through a chirped volume Bragg grating which was used as an external cavity output coupler. An average power of 208.2 mW, pulse energy of 321 pJ, and peak power of 30.3 W were achieved. Preliminary nonlinear imaging investigations indicate that this system is promising as a high peak-power pulsed light source for nonlinear bio-imaging applications across the 1.0 μm - 1.3 μm spectral range.