Taper-assisted polarisation compensation in efficiently fibre-coupled InP demultiplexer
A 8/spl times/2 nm polarisation independent InP-based demultiplexer operating at /spl sim/1.54 /spl mu/m with a low birefringence wide input waveguide has been produced by incorporating polarisation dispersion compensation into a highly birefringent waveguide. Mode converters were used in each arm of the grating to avoid transition losses. The fibre-waveguide insertion loss is 0.5 dB and, misalignment tolerance (at -1 dB) is 2.5 /spl mu/m. Crosstalk is as low as -30 dB.
We present what is to our knowledge the most complete 1-D numerical analysis of the evolution and the propagation ::: dynamics of an ultrashort laser pulse in a Ti:Sapphire laser oscillator. This study confirms the dispersion ::: managed model of mode-locking, and emphasizes the role of the Kerr nonlinearity in generating mode-locked ::: spectra with a smooth and well-behaved spectral phase. A very good agreement with experimental measurements ::: of pulse energy, spectrum, and temporal width of extracavity compressed pulses is found.