Silicon Carbide: Material Growth, Device Processing, and Applications.

The continuous demand for electronic devices operating at increasing current and power levels, as well as at high temperatures and in harsh environments, has driven research into wide-band gap (WBG) semiconductors over the last three decades [...

Materials and Processes for Schottky Contacts on Silicon Carbide.

Silicon carbide (4H-SiC) Schottky diodes have reached a mature level of technology and are today essential elements in many applications of power electronics. In this context, the study of Schottky barriers on 4H-SiC is of primary importance, since a deeper understanding of the metal/4H-SiC interface is the prerequisite to improving the electrical properties of these devices. To this aim, over the last three decades, many efforts have been devoted to developing the technology for 4H-SiC-based Schottky diodes.

Non-destructive characterization of rare-earth-doped optical fiber preforms.

We present a non-destructive optical technique for rare-earth-doped optical fiber preform inspection, which combines luminescence spectroscopy measurements, analyzed through an optical tomography technique, and ray-deflection measurements for calculating the refractive-index profile (RIP) of the sample. We demonstrate the technique on an optical fiber preform sample with a Yb-doped aluminosilicate core. The spatial distribution of the photoluminescence signals originating from Yb-single ions and from Yb-Yb cluster sites were obtained inside the core.

Radiation hardening techniques for Er/Yb doped optical fibers and amplifiers for space application.

We investigated the efficiencies of two different approaches to increase the radiation hardness of optical amplifiers through development of improved rare-earth (RE) doped optical fibers. We demonstrated the efficiency of codoping with Cerium the core of Erbium/Ytterbium doped optical fibers to improve their radiation tolerance. We compared the γ-rays induced degradation of two amplifiers with comparable pre-irradiation characteristics (~19 dB gain for an input power of ~10 dBm): first one is made with the standard core composition whereas the second one is Ce codoped.