title: Effect of wall tilt on the optical properties of integrated directional couplers.
abstract: The effect of wall tilt on the performance of directional couplers has been studied. There is a significant reduction in the coupling length as the tilt decreases when nonvertical walls, which are inherent in nearly all clean-room waveguide fabrication processes, are considered. Comparison of 90 degrees and 45 degrees coupling lengths reveals a difference of nearly a factor of 2 between them. Experimental data obtained with antiresonant reflecting optical waveguide directional couplers confirm that tilt effects should be considered in any device with large core thickness.
authors.forename: A
authors.initials: A
authors.lastname: Llobera
authors.forename: I
authors.initials: I
authors.lastname: Salinas
authors.forename: I
authors.initials: I
authors.lastname: Garcés
authors.forename: A
authors.initials: A
authors.lastname: Merlos
authors.forename: C
authors.initials: C
authors.lastname: Domínguez