POLARIZATION-INDEPENDENT WAVE-GUIDE MODULATOR USING A NOVEL QUANTUM-WELL WITH MASS-DEPENDENT WIDTH

We propose a novel quantum well (QW) structure with two or four thin barriers inserted in which effective width of the well is mass-dependent, It is very useful for polarization-independent optical modulation, Incorporation of tensile strain is also discussed for further improvement of the polarization insensitivity, Fabrication of a modulator with lattice-matched QW's results in 6-V switching voltage with more than -10-dB extinction (-30 dB maximum) for both TE and TM modes over 29-nm wavelength range, Compared with the quasiparabolic QW, this new quantum well has better fabrication tolerance, wider wavelength range of operation, and higher yield,