High confinement in silicon slot waveguides with sharp bends

Slot waveguides allow for high optical confinement in a planar optical waveguide. Here we show a method for maintaining this high degree of confinement in slot waveguides with sharp bends. This high confinement can be achieved by using an asymmetric slot-based structure, where the mode in the bend remains localized in the slot region. We show that the relative power inside the slot can be as high as 28% for a 1 mum radius bend in an air-clad silicon waveguide.