Polarization independent guided-wave optical modulators and switches

New low-voltage designs for polarization-independent interferometric optical modulators and coupled waveguide switches are described. Operation of these devices is based on TE-TM mode coupling via off-diagonal elements of the electrooptic tensor. Using a coupled mode analysis, it is shown that the refractive index change-length product is the same as for single-polarization modulators and switches which utilize diagonal electrooptic tensor elements. It is estimated that the use of TE-TM coupling can reduce the voltage-length product for polarization independent operation by a factor of 2 in LiNbO3and a factor of 2.9 in LiTaO3.

[1]  A. Johnston.  The Strain-Free Electro-Optic Effect in Single-Crystal Barium Titanate , 1965 .

[2]  H. Levinstein,et al.  Curie Temperature and Birefringence Variation in Ferroelectric Lithium Metatantalate as a Function of Melt Stoichiometry , 1967 .

[3]  G. D. Boyd,et al.  Refractive Index as a Function of Temperature in LiNbO3 , 1967 .

[4]  H. F. Taylor,et al.  Optical switching and modulation in parallel dielectric waveguides , 1973 .

[5]  A. Yariv,et al.  Guided wave optics , 1974 .

[6]  William Martin,et al.  A new waveguide switch/modulator for integrated optics , 1975 .

[7]  T. G. Giallorenzi,et al.  Performance limitations imposed on optical waveguide switches and modulators by polarization. , 1976, Applied optics.

[8]  William K. Burns,et al.  Interferometric waveguide modulator with polarization‐independent operation , 1978 .

[9]  R. Alferness,et al.  Polarization‐independent optical directional coupler switch using weighted coupling , 1979 .

[10]  R. Alferness,et al.  Efficient waveguide electro‐optic TE⇄TM mode converter/wavelength filter , 1980 .

[11]  Lawrence L. Buhl,et al.  Polarization independent optical filter using interwaveguide TE↔TM conversion , 1981 .

[12]  C. Mohr,et al.  Polarization-independent optical switch with multiple sections of Δβ reversal and a Gaussian taper function , 1982 .

[13]  Lawrence L. Buhl,et al.  Tunable electro‐optic waveguide TE〈–〉TM converter/wavelength filter , 1982 .

[14]  W. Burns,et al.  Polarization characteristics of LiNbO3 channel waveguide directional couplers , 1983 .

[15]  F. Heismann,et al.  Integrated‐optical frequency translator with stripe waveguide , 1984 .

[16]  B. E. Daymond-John,et al.  Temperature tuning of LiNbO3 electro-optic waveguide TE/TM mode convertors , 1984 .

[17]  Leon McCaughan.  Low-loss polarization-independent electrooptical switches at λ = 1.3µm , 1984 .

[18]  Michel Papuchon,et al.  Polarisation-independent modulators with Ti:LiNbO3 strip waveguides , 1984 .