A NEW SOLUTION TO WAVE-GUIDE EXCITATION SUPPRESSING THE EFFECTS OF THE RADIATED FIELD - APPLICATION TO THE Y-JUNCTION

When an integrated optical component is asymmetrically excited, a radi ated field is generated. Most of the rime, the energy carried by the r adiated field is lost. However, with high-level integration structures , this field can couple back into another waveguide and then disturb t he operating conditions of the whole component. An original waveguide geometry that rapidly removes this radiated field is thus proposed her e. The study of a specific Y-junction shows that it is possible to red uce by a factor of at least 30 the length of the Y-junction's straight waveguide. Computer modelling was performed with the radiation spectr um method (RSM), a new beam propagation method, perfectly suited to de aling with the field coming from guided and radiation modes. It gives us a good physical understanding of the light propagation.