Ultra-thin silicon/electro-optic polymer hybrid waveguide modulators

Journal Article · Mon Sep 21 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4931490· OSTI ID:22482147

Qiu, Feng; Spring, Andrew M. ^[1]; Sato, Hiromu ^[2]; Maeda, Daisuke; Ozawa, Masa-aki; Odoi, Keisuke ^[3]; Aoki, Isao; Otomo, Akira ^[4]; Yokoyama, Shiyoshi ^[1]

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1. Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasuga-koen Kasuga, Fukuoka 816-8580 (Japan)
2. Department of Molecular and Material Sciences, Kyushu University, 6-1 Kasuga-koen Kasuga, Fukuoka 816-8580 (Japan)
3. Nissan Chemical Industries, Ltd., 2-10-1 Tuboi Nishi, Funabashi, Chiba 274-8507 (Japan)
4. National Institute of Information and Communications Technology, 588-2 Iwaoka, Nishi-ku, Kobe 651-2492 (Japan)

Ultra-thin silicon and electro-optic (EO) polymer hybrid waveguide modulators have been designed and fabricated. The waveguide consists of a silicon core with a thickness of 30 nm and a width of 2 μm. The cladding is an EO polymer. Optical mode calculation reveals that 55% of the optical field around the silicon extends into the EO polymer in the TE mode. A Mach-Zehnder interferometer (MZI) modulator was prepared using common coplanar electrodes. The measured half-wave voltage of the MZI with 7 μm spacing and 1.3 cm long electrodes is 4.6 V at 1550 nm. The evaluated EO coefficient is 70 pm/V, which is comparable to that of the bulk EO polymer film. Using ultra-thin silicon is beneficial in order to reduce the side-wall scattering loss, yielding a propagation loss of 4.0 dB/cm. We also investigated a mode converter which couples light from the hybrid EO waveguide into a strip silicon waveguide. The calculation indicates that the coupling loss between these two devices is small enough to exploit the potential fusion of a hybrid EO polymer modulator together with a silicon micro-photonics device.

• OSTI ID: 22482147
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 12 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CLADDING
DESIGN
ELECTRIC POTENTIAL
ELECTRODES
EQUIPMENT
FILMS
HYBRIDIZATION
LOSSES
MACH-ZEHNDER INTERFEROMETER
OPTICAL MODES
POLYMERS
POTENTIALS
SCATTERING
SILICON
THICKNESS
WAVEGUIDES
WIDTH