Adiabatically tapered directional coupling between dielectric waveguides


  • Ottokar Leminger,

  • Gerhard Zesch


Conventional dielectric dual-channel directional couplers used in integrated optics are subject to severe tolerance restrictions on the waveguide parameters, in order to guarantee nearly complete power transfer. These restrictions are relaxed considerably by tapering suitably both waveguides. Such adiabatically tapered couplers can be designed easily along the beam propagation method combined with the effective index method. Computer simulations confirm their advantage.