Title :
Optical analysis of mushroom-type traveling wave electroabsorption modulatorsusing full-vectorial finite difference method
Author :
Abedi, K. ; Ahmadi, V. ; Moravvej-Farshi, Mohammad Kazem ; Razaghi, M.
Author_Institution :
Dept. of Electr.&Comput. Eng., Shahid Beheshti Univ., Tehran, Iran
Abstract :
Larger width of P-cladding layer in p-i-n waveguide of traveling wave electroabsorption modulator (TWEAM) results in lower resistance and microwave propagation loss which provides an enhanced high speed electro-optical response. In this paper, a full-vectorial finite-difference-based optical mode solver is presented to analyze mushroom-type TWEAM. The important parameters in the high-frequency TWEAM design such as optical effective index and transverse mode confinement factor are calculated. The modulation response of mushroom-type TWEAM is calculated by considering interaction between microwave and optical fields in waveguide and compared with conventional ridge-type TWEAM. The calculated 3dB bandwidths for ridge-type and mushroom-type TWEAM are about 139 GHz and 166 GHz for 200 mum and 114 GHz and 126 GHz for 300 mum waveguide length, respectively.
Keywords :
electroabsorption; finite difference methods; microwave photonics; microwave propagation; optical modulation; optical waveguides; travelling wave tubes; P-cladding layer; electro-optical response; full-vectorial finite-difference method; microwave fields; microwave propagation loss; mushroom-type TWEAM; optical effective index; optical fields; optical mode solver; p-i-n waveguide; size 200 mum; size 300 mum; transverse mode confinement factor; traveling wave electroabsorption modulator; Bandwidth; Electrooptic modulators; Electrooptical waveguides; Finite difference methods; High speed optical techniques; Optical design; Optical modulation; Optical waveguides; PIN photodiodes; Propagation losses; Electroabsorption; Full-vectorial Finite difference method; Mushroom-type TWEAM; Traveling wave modulator;
Conference_Titel :
Numerical Simulation of Optoelectronic Devices, 2009. NUSOD 2009. 9th International Conference on
Conference_Location :
Gwangju
Print_ISBN :
978-1-4244-4180-8
DOI :
10.1109/NUSOD.2009.5297233
