MULTIPLE WAVELENGTH LIGHT-SOURCE USING AN ASYMMETRIC WAVE-GUIDE COUPLER

We obtained multiple wavelength light emission from a coupled waveguid e structure formed from a conventional waveguide and a vertical cavity resonator. The cavity and quarter-wave mirrors are optimized to act a s another waveguide, thus forming an asymmetric directional coupler. T his asymmetry between the waveguide and the vertical cavity causes wav elength selectivity in the cavity light emission. By tapering the cavi ty, the phase-matched wavelength becomes a function of position, and p umping different regions along the length of the waveguides causes dif ferent wavelengths to be emitted from the device. We obtained narrow-b and luminescence with a minimum width of 1 nm using a 75-angstrom quan tum well in a GaAs/AlGaAs vertical cavity structure coupled to a low i ndex polymer waveguide.