Nonlinear silicon photonics

Session - Silicon Photonics and Photonic Integrated Circuits IIAn intriguing optical property of silicon is that it exhibits a large third-order optical nonlinearity, with orders-ofmagnitude larger than that of silica glass in the telecommunication band. This allows efficient nonlinear optical interaction at relatively low power levels in a small footprint. Indeed, we have witnessed a stunning progress in harnessing the Raman and Kerr effects in silicon as the mechanisms for enabling chip-scale optical amplification, lasing, and wavelength conversion - functions that until recently were perceived to be beyond the reach of silicon. With all the continuous efforts developing novel techniques, nonlinear silicon photonics is expected to be able to reach even beyond the prior achievements. Instead of providing a comprehensive overview of this field, this manuscript highlights a number of new branches of nonlinear silicon photonics, which have not been fully recognized in the past. In particular, they are two-photon photovoltaic effect, mid-wave infrared (MWIR) silicon photonics, broadband Raman effects, inverse Raman scattering, and periodically-poled silicon (PePSi). These novel effects and techniques could create a new paradigm for silicon photonics and extend its utility beyond the traditionally anticipated applications. © 2010 Copyright SPIE - The International Society for Optical Engineering.published_or_final_versionThe 2010 Conference of the International Society for Optical Engineering (SPIE) Photonics Europe, Brussels, Belgium, 12-16 April 2010. In Proceedings of SPIE, 2010, v. 7719, article no. 77190

Specific composition and morphological peculiarities of endemic monogenean parasites of freshwater fishes of Iran

Result obtained during ten years research work (1990-2000) on distribution of monogenean fauna Iranian fishes indicates that its composition of monogenean fauna of Iranian fishes depends on their habit and since Iran includes three different zoogeographical zones with highly endemic fish hosts, its monogenean parasites have specific composition. The Caspian fauna is characterized by relatively great diversity of monogenean species (eleven genera and at least forty-eight species). Presence of some species with sphymoid type of anchors is one of its speciation. The Iranian part of Mezopotomian (Tigris) fauna (six genera and at least twenty-six species) is characterized by distinct monogenean parasites, for instance, presence of Dogielius type of anchors and prevalence of Dactylogyrus spp. with morphilogical peculiarities not similar to Sarmatian fauna. The most of its specific character is the shape of dorsal and ventral bar in Dactylogyrus species found in the Tigris Zone. Endemism in the a forsaid zone is high therefore species of Dactylogyrus will be increased more. The oriental monogenean fauna of Iran (three genera and at least eleven species) shows special characteristics, amongthem, the presence of one connective dorsal bar only, presence of varicorhinoid type of bar and haptor would suggest that aforesaid zone of Iran has been influenced by the Indian fauna

Green silicon photonics

Silicon photonics have provided low-cost communication components for Internet applications and are now aimed towards providing environmentally friendly and green optical solutions. The need for energy-efficient photonics is due to the excessive energy dissipated in advanced electronics and an increase in power density that has posed a challenge to the most advanced chip-cooling technologies. The two-photon absorption (TPA)-generated free carriers need to be actively removed from the waveguide cover to eliminate any event of light absorption and a subsequent conversion to heat. Researchers have proposed an electro-optic modulator that takes advantage of the two-photon photovoltaic (TPPV) effect to attain negative static power dissipation. Photovoltaic power converters (PPC) are used for remote power delivery and are optimized for a wavelength range from 1,200 to 1,550 nm.published_or_final_versio

Occurrence and description of Dactylogyrus sphyrna Linstow, 1878 (Monogenea: Dactylogyride) on the gills of an Iranian endemic fish Leucisucs persidis Coad, 1981 as a new host

Leuciscus persidis as Iranian endemic fish in Kaftar lake and its headwaters (Mesopotamian subregion, Kor-Neiriz basin and Shadkam river) has been infected with a species of Dactylogyrus sphyrna. Comparison of collected parasites with Euro-Asian subregion showed that the similarity of them is more than their differences, although a little difference between them was observed. In this paper also introduce of Dactylogyrus sphyrna parasite to the new host is discussed

Periodically poled silicon (PePSi) for efficient and electronically-tuned nonlinear optics in silicon

Periodically poled silicon (PePSi) induces substantial 2nd order optical nonlinearity and at the same time achieves quasi-phase matching. PePSi is made by alternating strain gradients along the waveguide using periodic arrangement of stressed cladding layers. © 2013 OSA.published_or_final_versio

Extreme Value Statistics in Silicon Photonics

L-shape probability distributions are extremely non-Gaussian functions that have been surprisingly successful in describing the occurrence of extreme events ranging from stock market crashes, natural disasters, structure of biological systems, fractals, and optical rogue waves. We show that fluctuations in stimulated Raman scattering, as well as in coherent anti-Stokes Raman scattering, in silicon can follow extreme value statistics and provide mathematical insight into the origin of this behavior

Short communication: Monogenean species from freshwater fishes of Zanjan province, Iran

This parasitological research was conducted from September 2002 to August 2003 on the freshwater fishes in Zanjan province. Totally 155 fishes including Capoeta capoeta idellaI (91), Carassius auratus (8), Leuciscus cephalus (18), Ctenopharyngodon idella (10), Barbus lacerta (8), Allburnoides bipunctatus (10) and Alburnus filippi (10), were seined from five different stations. The fishes were transferred to Laboratory of Aquatic Organisms Research in Science Faculty of Shahid Beheshti University. The skin and gills of fishes were studied under light and stereomicroscope. The identified monogenean parasites included seven Dactylogyrus species as: D. chramuli, D. gracilis, D. Lenkorani and D. pulcher from Capoeta capoeta gracilis; D. lamellatus from Ctenopharyngodon idella; D. goktschaicus from Barbus lacerta and D. vistulae from Albunoides bipunctatus and Alburnus filippi. Various Gyrodactylus spp. from skin and gills of different fish specimens and one Paradiplozoon sp. from gill of Alburnoides bipunctatus were observed. This is the first parasitological investigation that has been done on the freshwater fishes of Zanjan province