Title :
Electrooptic polymer modulators operating in both TE and TM modes incorporating a vertically tapered cladding
Author :
Oh, Min-Cheol ; Hwang, Wol-Yon ; Lee, Hyang-Mok ; Han, Seon-Gyu ; Won, Yong-Hyub
Author_Institution :
Electron. & Telecommun. Res. Inst., Taejon, South Korea
Abstract :
We propose a modified electrooptic (EO) PMMA polymer waveguide structure supporting both TE and TM modes in spite of the large birefringence induced by the poling. A vertically tapered structure is employed to connect a single-mode rib waveguide and a confinement-enhanced rectangular buried waveguide. This waveguide structure can be easily fabricated by a two-step reactive ion etching (RIE) process with a shadow mask. To demonstrate TE/TM confinement and single-mode operation, Mach-Zehnder intensity modulators are fabricated by incorporating the proposed waveguide structure. The extinction ratio is better than -15 dB, which proves the single-mode operation. Half-wave voltages for TM and TE modes are 6 and 24 V, respectively.
Keywords :
birefringence; claddings; electro-optical modulation; integrated optics; masks; optical fabrication; optical polymers; optical waveguides; rectangular waveguides; sputter etching; 24 V; 6 V; Mach-Zehnder intensity modulators; PMMA; TE modes; TE/TM confinement; TM modes; confinement-enhanced rectangular buried waveguide; electrooptic polymer modulators; extinction ratio; half-wave voltages; large birefringence; modified electrooptic polymer waveguide structure; poling; reactive ion etching; shadow mask; single-mode operation; single-mode rib waveguide; two-step RIE process; vertically tapered cladding; vertically tapered structure; waveguide structure; Birefringence; Electrooptic modulators; Electrooptical waveguides; Etching; Extinction ratio; Intensity modulation; Polymers; Rectangular waveguides; Tellurium; Voltage;
Journal_Title :
Photonics Technology Letters, IEEE
