Further computation indicates that the ferrite slabs loaded ridged waveguide has broadband frequency properties and the grooved waveguide has greater differential phase shift.

To achieve high optical power as well as low vertical divergence angle,a new kind of optim ized large opti- cal cavity (L OC) structure is applied to a ridge waveguide 980 nm In Ga As/ Ga As/ Al Ga As m ulti- quantum well laser.

It is found that optimization of the structure parameters of ridge waveguide (RWG) can decrease the threshold current of RWG laser diode.

5 μm InGaAsP integrated device was fabricated by using the ridge waveguide.

High-power ridge-waveguide tapered InGaAs-AlGaAs lasers emitting at 980nm were fabricated.

By etching a second-order grating directly into the Al-free optical waveguide region of a ridge-waveguide(RW) AlGaInAs/AlGaAs distributed feedback(DFB) laser diode,a front facet output power of 30mW is obtained at about 820nm with a single longitudinal mode.

The lifetime of free carriers in a silicon-on-insulator(SOI) rib waveguide,which is used for Raman amplification,is studied in connection with the nonlinear optical loss.

The coupling efficiency between a rib waveguide based silicononinsulator(SOI) and a singlemode fiber(SMF) was improved by using an optimally designed mode transformer.

Based on the comparison between two different single mode conditions for rib waveguides with large cross section,the conditions given by Pogossian et al and its errors are analysed.