Ultra High Speed Semiconductor Electrooptic Modulator Devices for Gigahertz Operation in Optical Communication Systems (original) (raw)
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IEEE/OSA Journal of Lightwave Technology, 2012
We present a comprehensive modeling study of a high-speed gallium arsenide electro-optic modulator with ultralow switching voltages and large modulation bandwidths enabled by transparent conducting (TC) electrodes. The driving voltage, optical insertion loss, and modulation bandwidth of the TC-enabled modulator are systematically analyzed. Optimized designs for both a top-down and a side conduction geometry using Ta2O5 as both buffer and side cladding layers are presented. The results predict half-wave voltages from 0.5 down to 0.2 V, optical insertion losses of 6-10 dB, and optical 3 dB modulation bandwidths from 25-50 GHz for a top-down conduction geometry and 15-30 GHz for a side conduction geometry, assuming that proper impedance transforming parts and terminations are used. The use of benzocyclobutane as side cladding layers in the top-down conduction geometry to realize direct impedance matching was also explored. The corresponding modulation bandwidths are 13 GHz for 0.5 V case and 6 GHz for 0.2 V case, mainly limited by RF-optical wave velocity mismatch.
Photonics
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Microwave and Optical Technology Letters, 2010
Electro‐optic modulators are key components in high bit‐rate optical transmissions. Decreasing the manufacturing cost without damage on performances is one of the most challenging issues for such components. We demonstrate that the electro‐optic modulators based on polymer are compatible with high bandwidth requirements. Indeed, according to the results obtained by numerical simulation and partly validated by experiments, with the via‐free GCPW‐MS‐GCPW electrodes proposed and analyzed in this article, the (400 MHz–67 GHz) bandwidth is achievable with electro‐optic modulators based on suitable polymers. These encouraging results are very useful for low‐cost mass production of polymer‐based electro‐optic modulators for a wide range of applications: digital and analogue high bit‐rate transmissions.© 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1078–1082, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25112