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The photoinduced load obtained by illuminating the open end of a microstrip line on a semiconductor substrate is reported to be dependent on the nature of the metal/semiconductor contact. We have used the R//C model to study the photoinduced behavior according to the applied dc voltages, optical powers, and microwave signal frequency. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 257–261, 2001. [ABSTRACT FROM AUTHOR]

We have shown that, if a microstrip line deposited on silicon is illuminated at its end, a nonlinear load is obtained which behaves in microwave like a “photoinduced varactor.” We have obtained this result experimentally, and by solving the Poisson's equation and the two carrier continuity equations. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 10–13, 2000. [ABSTRACT FROM AUTHOR]

We present a new large/small signal equivalent circuit for semiconductor lasers, valid for above- as well as below-threshold operating conditions, based on the monomode rate equations and a polynomial approximation of Fermi integral. The model is thus valid for conditions of large injection. Results obtained by this model match perfectly those obtained by numerical integration of the rate equations. The equivalent circuit is easy to implement and solve on a nonlinear circuit analysis software such as SPICE and consequently allows the study of the parasitic effects as well as the laser behavior in complex circuits. Comparison between this model and previously published models is presented. The model is applied to the study of various heterojunction laser diodes, the experimental results of which have been published elsewhere. [ABSTRACT FROM AUTHOR]

We present the design and realization of a 1×4 switching matrix, based on an electro-optical directional coupler. This matrix is devoted to true time delay systems. It is characterized by an original topology that reduces global power consumption down to 20 mW. Fiber-to-fiber losses are 15 dB, and the crosstalk is lower than -20 dB. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 18: 243–246, 1998. [ABSTRACT FROM AUTHOR]

A three-terminal edge-coupled InGaAs/InP phototransistor is reported. A dc photocurrent gain near 60 and an optical unity gain frequency of 40 GHz were measured. The mixing of a modulated optical signal and a microwave signal applied on the base terminal is presented. Optical and electrical modeling are used to analyze and improve the device performances. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 17: 408–412, 1998. [ABSTRACT FROM AUTHOR]

It is shown that local and large lattice mismatch epitaxies could be useful techniques for the fabrication of optoelectronic integrated circuits. As an example, we fabricated a monolithic resonant photoreceiver which associates a long-wavelength metal-semiconductor-metal photodetector, a GaAs MESFET preamplifier, and an inductor. The GaAs / GaInAs heteroepitaxy needed for the photodetector wax selectively grown using a SiO[sub2] mask and the entire circuit was fabricated on a silicon substrate. Compared to a PIN photodiode loaded with a 50-ω resistor, more than 10 dB gain was measured at 7 GHz in a microwave optical link. [ABSTRACT FROM AUTHOR]

We have measured the noise performance of GaInAs PIN photodiodes in the microwave frequency range. We show that the frequency response of the photodetector can be deduced from their photocurrent shot noise spectra. The noise level has been measured using a setup which is based on heterodyne microwave mixing. [ABSTRACT FROM AUTHOR]