Title :
Electro-optic modulator coupling loss improvement by tapering waveguides and fibers
Author :
Yacoubian, Araz ; Lin, Weiping ; Olson, David ; Shi, Yongqiang ; Bechtel, James H.
Author_Institution :
IPITEK, Carlsbad, CA, USA
Abstract :
Polymer based electro-optic (EO) modulators have the potential to provide low cost and lightweight alternative for antenna remoting and RF links because of their wide bandwidth (>100 GHz) and low drive voltage (Vπ<1 V) capabilities. Low noise figure and low power consumption systems require low insertion loss modulators. There are two major causes of loss in EO modulators: waveguide propagation loss (typically 1 dB/cm), and fiber-to-waveguide coupling loss. In this paper we investigate methods to minimize fiber-to-waveguide coupling loss which is mainly due to mode size mismatch. Pigtails using standard single mode fiber produce coupling loss on the order of 3 to 5 dB/connection. In order to improve mode size matching yet maintain low drive voltage, we incorporate waveguide and fibers tapers. Experimental results indicate improvement of up to 3 dB/connection (6 dB/device) using waveguide tapers, and up to 2 dB/connection (4 dB/device) using fiber tapers
Keywords :
Mach-Zehnder interferometers; electro-optical modulation; integrated optics; optical fibres; optical losses; optical polymers; optical waveguides; 1 V; 100 GHz; coupling loss improvement; electro-optic modulator; fiber-to-waveguide coupling loss; fibre tapers; low insertion loss modulators; mode size mismatch; polymer based EO modulators; waveguide tapers; Antennas and propagation; Bandwidth; Costs; Electrooptic modulators; Electrooptical waveguides; Low voltage; Optical fiber devices; Polymers; Propagation losses; Radio frequency;
Conference_Titel :
Aerospace Conference, 2001, IEEE Proceedings.
Conference_Location :
Big Sky, MT
Print_ISBN :
0-7803-6599-2
DOI :
10.1109/AERO.2001.931378