Short waveguide microcavity with adiabatic modal conversion

A waveguide based microcavity with short taper has been realized by incorporating four identical 8-groove tapers at the four reflector extremities. The microstructure has an overall length of 14 /spl mu/m and consists of two first-order Bragg mirrors with very narrow slits (90 nm) and of four series of slits with progressively varying widths (tapers). A comparison with a non-tapered cavity evidences the beneficial effect of the taper approach on both the Q factor and the peak transmission at resonance.