title: Enhanced conductivity of sol-gel silica cladding for efficient poling in electro-optic polymer/TiO2 vertical slot waveguide modulators.
abstract: We report the enhanced conductivity of sol-gel silica under-cladding for efficient poling of electro-optic (EO) polymer in a hybrid EO polymer/TiO2 vertical slot waveguide modulator. The electrical volume conductivity of sol-gel silica cladding increases approximately 30 times when the calcining time of the cladding layer is critically reduced to 45 minutes, which increases the in-device EO coefficient of the 600-nm-thick EO polymer film in modulators and reduces the lower halfwave voltage (Vπ) of the modulators. The lowest driving voltage (Vπ) of the TiO2 slot waveguide modulator is 2.0 V for an electrode length (Le) of 10 mm and wavelength of 1550 nm (VπLe = 2.0 V·cm) for the low-index guest-host EO polymer SEO125. The optical propagation loss is reduced to 7 dB/cm.
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Enami
authors.forename: Youssef
authors.initials: Y
authors.lastname: Jouane
authors.forename: Jingdong
authors.initials: J
authors.lastname: Luo
authors.forename: Alex K-Y
authors.initials: AK
authors.lastname: Jen
mesh_terms: D004553:Electric Conductivity; D004581:Electronics; D055095:Optics and Photonics / Q000295:instrumentation*; D044367:Phase Transition; D011108:Polymers / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D011108:Polymers; C009495:titanium dioxide; D012822:Silicon Dioxide; D014025:Titanium