title: Perturbation analysis of polarization splitting directional couplers.
abstract: We present a detailed perturbation analysis of the recently proposed polarization splitting directional coupler configuration consisting of two interacting optical waveguides with a thin layer of metal between the two waveguides. We have carried out numerical calculations of extinction ratios by the approximate perturbation method and compared the results with those obtained by a more rigorous matrix method developed earlier by A. K. Ghatak et al., IEEE/OSA J. Lightwave Technol.LT-5, 660 (1987). We also studied the tolerances required for the device. We carried out calculations for gold and aluminum and have shown that the proposed device has extinction ratios of about -22 dB for gold and -31 dB for aluminum.
authors.forename: S
authors.initials: S
authors.lastname: Diggavi
authors.forename: K
authors.initials: K
authors.lastname: Thyagarajan
authors.forename: A K
authors.initials: AK
authors.lastname: Ghatak