title: 30GHz Ge electro-absorption modulator integrated with 3 μm silicon-on-insulator waveguide.
abstract: We demonstrate a compact waveguide-based high-speed Ge electro-absorption (EA) modulator integrated with a single mode 3 µm silicon-on-isolator (SOI) waveguide. The Ge EA modulator is based on a horizontally-oriented p-i-n structure butt-coupled with a deep-etched silicon waveguide, which transitions adiabatically to a shallow-etched single mode large core SOI waveguide. The demonstrated device has a compact active region of 1.0 × 45 µm(2), a total insertion loss of 2.5-5 dB and an extinction ratio of 4-7.5 dB over a wavelength range of 1610-1640 nm with -4V(pp) bias. The estimated Δα/α value is in the range of 2-3.3. The 3 dB bandwidth measurements show that the device is capable of operating at more than 30 GHz. Clear eye-diagram openings at 12.5 Gbps demonstrates large signal modulation at high transmission rate.
authors.affiliation: Kotura Inc., 2630 Corporate Place, Monterey Park, California 91754, USA. nfeng@kotura.com
authors.forename: Ning-Ning
authors.initials: NN
authors.lastname: Feng
authors.forename: Dazeng
authors.initials: D
authors.lastname: Feng
authors.forename: Shirong
authors.initials: S
authors.lastname: Liao
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Po
authors.initials: P
authors.lastname: Dong
authors.forename: Hong
authors.initials: H
authors.lastname: Liang
authors.forename: Cheng-Chih
authors.initials: CC
authors.lastname: Kung
authors.forename: Wei
authors.initials: W
authors.lastname: Qian
authors.forename: Joan
authors.initials: J
authors.lastname: Fong
authors.forename: Roshanak
authors.initials: R
authors.lastname: Shafiiha
authors.forename: Ying
authors.initials: Y
authors.lastname: Luo
authors.forename: Jack
authors.initials: J
authors.lastname: Cunningham
authors.forename: Ashok V
authors.initials: AV
authors.lastname: Krishnamoorthy
authors.forename: Mehdi
authors.initials: M
authors.lastname: Asghari
mesh_terms: D000042:Absorption; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D005857:Germanium / Q000737:chemistry*; D008422:Materials Testing; D055096:Optical Devices; D055095:Optics and Photonics; D010825:Physics / Q000379:methods*; D012031:Refractometry / Q000295:instrumentation; D012825:Silicon / Q000737:chemistry*
chemical_list: D005857:Germanium; D012825:Silicon