Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446934
J. Galisteo‐López
Summary form only given. Artificial opals are nowadays acknowledged as ideal playgrounds where the optical properties of three dimensional (3D) photonic crystals can be tested. Over the past few years several works have demonstrated that a strong enhancement of the interaction between light and matter can be achieved with these systems. These type of nano-structured materials tend to grow in an FCC lattice with the (111) planes parallel to the sample surface. This characteristic fact imposes some restrictions on their dispersion relation (and hence on its optical properties) which are usually compensated for by introducing modifications in their topology by infiltrating them with high refractive index materials or introducing controlled defects. In this work we present recent results regarding the optical characterization of artificial opals containing planar defects as well as opals oriented along crystallographic directions other than the (111). The amplitude and phase of light transmitted through the samples is measured providing us with valuable information regarding the way light propagates in these structures. Our results evidence that besides the well known response in the surroundings of the stop-band, these structures can exhibit much more exciting properties such as superluminal propagation with negative group velocities.
{"title":"New routes for exploiting the optical properties of artificial opals","authors":"J. Galisteo‐López","doi":"10.1109/ICTONMW.2007.4446934","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446934","url":null,"abstract":"Summary form only given. Artificial opals are nowadays acknowledged as ideal playgrounds where the optical properties of three dimensional (3D) photonic crystals can be tested. Over the past few years several works have demonstrated that a strong enhancement of the interaction between light and matter can be achieved with these systems. These type of nano-structured materials tend to grow in an FCC lattice with the (111) planes parallel to the sample surface. This characteristic fact imposes some restrictions on their dispersion relation (and hence on its optical properties) which are usually compensated for by introducing modifications in their topology by infiltrating them with high refractive index materials or introducing controlled defects. In this work we present recent results regarding the optical characterization of artificial opals containing planar defects as well as opals oriented along crystallographic directions other than the (111). The amplitude and phase of light transmitted through the samples is measured providing us with valuable information regarding the way light propagates in these structures. Our results evidence that besides the well known response in the surroundings of the stop-band, these structures can exhibit much more exciting properties such as superluminal propagation with negative group velocities.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131417467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446941
H. Aourag
/t.
/ t。
{"title":"Left handed photonic band gap materials: An issue in transparent optical networks","authors":"H. Aourag","doi":"10.1109/ICTONMW.2007.4446941","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446941","url":null,"abstract":"/t.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132380723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446971
A. Louhadj, H. Barhoumi, H. Abid
A method for calculating the electronic structure of the quaternary alloy GaAlInAs is presented with zinc blende structure. We have used the empirical pseudo-potential method coupled with the virtual crystal approximation (VCA). The electronic structures are studied for GaAlInAs (x = 0.24, y = 0.24) and GaAlInAs lattice matched to InP as well GaAs. In addition a method for calculating the refractive index is presented, which we used the Sellmeir model. The composition dependence of the refractive index is discussed, the results indicate that refractive index decrease with alloying composition of the quaternary alloy GaAlInAs lattice matched to InP and GaAs.
提出了一种以闪锌矿结构计算四元合金GaAlInAs电子结构的方法。我们使用了经验伪势法与虚晶体近似(VCA)相结合。研究了GaAlInAs (x = 0.24, y = 0.24)的电子结构，以及与InP和GaAs匹配的GaAlInAs晶格。此外，本文还提出了一种利用Sellmeir模型计算折射率的方法。讨论了折射率的成分依赖关系，结果表明，与InP和GaAs相匹配的GaAlInAs晶格的合金成分使折射率降低。
{"title":"Pseudo-potential calculations of the electronic and optical properties of GaxAlyIn1–x–yAs","authors":"A. Louhadj, H. Barhoumi, H. Abid","doi":"10.1109/ICTONMW.2007.4446971","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446971","url":null,"abstract":"A method for calculating the electronic structure of the quaternary alloy GaAlInAs is presented with zinc blende structure. We have used the empirical pseudo-potential method coupled with the virtual crystal approximation (VCA). The electronic structures are studied for GaAlInAs (x = 0.24, y = 0.24) and GaAlInAs lattice matched to InP as well GaAs. In addition a method for calculating the refractive index is presented, which we used the Sellmeir model. The composition dependence of the refractive index is discussed, the results indicate that refractive index decrease with alloying composition of the quaternary alloy GaAlInAs lattice matched to InP and GaAs.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132125952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446928
W. Fourati, R. Attia, M. Ammar
We show the feasibility of two-dimensional structures air/LiNbO3 which ensures the achievement of ordered functions such as dynamic filtering. A study by FDTD (Finite Difference Time Domain) simulation shows that a variation of 0.005 of the refractive index in LiNbO3 allows a linear shifting of the Photonic Band Gap of 4.1 nm.
{"title":"Two-dimensional photonic crystals in lithium niobate (LiNbO3)","authors":"W. Fourati, R. Attia, M. Ammar","doi":"10.1109/ICTONMW.2007.4446928","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446928","url":null,"abstract":"We show the feasibility of two-dimensional structures air/LiNbO3 which ensures the achievement of ordered functions such as dynamic filtering. A study by FDTD (Finite Difference Time Domain) simulation shows that a variation of 0.005 of the refractive index in LiNbO3 allows a linear shifting of the Photonic Band Gap of 4.1 nm.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132663598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446951
S. Triki, M. Najjar, H. Rezig
An optical demultiplexer based on the multimode interference (MMI) coupler is demonstrated in this work. The proposed device is designed and simulated by showing the optimum parameters for the structure (length of MMI region, the separation and the angle of the arm). The calculated results show that the crosstalk of the coupler is about -19.4 and -11.66 dB for 1310 and 1550 nm respectively. The insertion Loss is around 1.5-2.5 dB for demultiplexing operation.
{"title":"Optimization of MMI-WDM demultiplexer by using BPM method","authors":"S. Triki, M. Najjar, H. Rezig","doi":"10.1109/ICTONMW.2007.4446951","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446951","url":null,"abstract":"An optical demultiplexer based on the multimode interference (MMI) coupler is demonstrated in this work. The proposed device is designed and simulated by showing the optimum parameters for the structure (length of MMI region, the separation and the angle of the arm). The calculated results show that the crosstalk of the coupler is about -19.4 and -11.66 dB for 1310 and 1550 nm respectively. The insertion Loss is around 1.5-2.5 dB for demultiplexing operation.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114066156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446937
M. Bozzetti, G. Calò, A. D’orazio, M. De Sario, L. Mescia, V. Petruzzelli, F. Prudenzano
A brief overview on integrated optical sensors for environment monitoring is given. A variety of optical transducers is illustrated and the interaction between the evanescent electromagnetic field and the polluted medium under detection is described in detail. A chemically selective layer on the waveguide core binds and/or absorb the polluting molecules contained in the liquid or gaseous sample. The variation of the real and/or the imaginary part of the sensitive layer refractive index affects the penetration depth of the evanescent field of the core guided waves. Many sensor, based on this principle, configurations have been developed for chemical and biochemical applications. As an example, in this review the main numerical results pertaining to integrated optical sensors for hydrocarbon detection in water are illustrated. Various kind of planar waveguide sensors are designed by considering a polydimethylsiloxane (PDMS) polymeric overlay. The waveguide cross-section is refined to enhance the evanescent optical field, which interacts with the surrounding polymeric overlay and effects the waveguide sensor performance. The sensor based on this approach detects changes in the waveguide attenuation constant induced by the penetration of the hydrocarbons into the PDMS. The obtained results show that the proposed sensors could represent good candidates in terms of detection sensitivity and, in addition, to identify different analytes mixed in water solution. .
{"title":"Integrated optical sensor for environment monitoring","authors":"M. Bozzetti, G. Calò, A. D’orazio, M. De Sario, L. Mescia, V. Petruzzelli, F. Prudenzano","doi":"10.1109/ICTONMW.2007.4446937","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446937","url":null,"abstract":"A brief overview on integrated optical sensors for environment monitoring is given. A variety of optical transducers is illustrated and the interaction between the evanescent electromagnetic field and the polluted medium under detection is described in detail. A chemically selective layer on the waveguide core binds and/or absorb the polluting molecules contained in the liquid or gaseous sample. The variation of the real and/or the imaginary part of the sensitive layer refractive index affects the penetration depth of the evanescent field of the core guided waves. Many sensor, based on this principle, configurations have been developed for chemical and biochemical applications. As an example, in this review the main numerical results pertaining to integrated optical sensors for hydrocarbon detection in water are illustrated. Various kind of planar waveguide sensors are designed by considering a polydimethylsiloxane (PDMS) polymeric overlay. The waveguide cross-section is refined to enhance the evanescent optical field, which interacts with the surrounding polymeric overlay and effects the waveguide sensor performance. The sensor based on this approach detects changes in the waveguide attenuation constant induced by the penetration of the hydrocarbons into the PDMS. The obtained results show that the proposed sensors could represent good candidates in terms of detection sensitivity and, in addition, to identify different analytes mixed in water solution. .","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128927771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446917
M. Wojdyla, M. Rebarz, B. Derkowska, W. Bala, Z. Essaidi, M. Bakasse
In this paper, photoluminescence (PL), transmittance (T) and absorption (A) measurements have been performed for the first time on metallophthalocyanines (MPc; M = Zn, Co, Mg, Cu) thin layers grown by quasi molecular beam evaporation on quartz substrates. Investigated films of ZnPc and MgPc show PL emission from the violet to near-IR region in the wide temperature range 13 K-320 K. While the two others show a rather weak emission. Measurements have been carried out in the 350-1150 nm spectral range. The photoluminescence spectra exhibit seven transitions. Some bands have been appeared only at certain temperature range. Below and above this temperature range, these bands have been disappeared. The changes of intensity, band position and broadening versus temperature have been investigated. A multi level model has been proposed to explain the photophysical processes and temperature dependence of PL spectra.
{"title":"The temperature dependence of photoluminescence and absorption spectra of MPc (M = Zn, Co, Mg, Cu) thin films","authors":"M. Wojdyla, M. Rebarz, B. Derkowska, W. Bala, Z. Essaidi, M. Bakasse","doi":"10.1109/ICTONMW.2007.4446917","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446917","url":null,"abstract":"In this paper, photoluminescence (PL), transmittance (T) and absorption (A) measurements have been performed for the first time on metallophthalocyanines (MPc; M = Zn, Co, Mg, Cu) thin layers grown by quasi molecular beam evaporation on quartz substrates. Investigated films of ZnPc and MgPc show PL emission from the violet to near-IR region in the wide temperature range 13 K-320 K. While the two others show a rather weak emission. Measurements have been carried out in the 350-1150 nm spectral range. The photoluminescence spectra exhibit seven transitions. Some bands have been appeared only at certain temperature range. Below and above this temperature range, these bands have been disappeared. The changes of intensity, band position and broadening versus temperature have been investigated. A multi level model has been proposed to explain the photophysical processes and temperature dependence of PL spectra.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127485832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-12-01DOI: 10.1109/ICTONMW.2007.4446920
S. Shettigar, G. Umesh, P. Poornesh, Y. Murthy*
We report the investigation of third order optical nonlinearity of 2,4,6-tri-(p-hyptoyoxylphenyl) pyrilium tetraborate doped PMMA using nanosecond laser pulses at 532 nm wavelength by employing Z-Scan technique. To see the effect of polymer host, the results have been compared with the pure dopant. The material shows a large negative nonlinearity with real and imaginary parts of chi(3) are - 3.31times10-14 esu and 0.73times10-14 esu respectively. Excited state absorption cross-section is found to be 3.41times10-48 cm4.s/photon in PMMA host. The magnitude of third order nonlinear parameters increases when the compound is doped into PMMA matrix because of change in the conformation of chain geometry as a result of charge transfer processes. The values are comparable with a best known nonlinear liquid crystal molecule namely, 4-cyano-4'-n-pentylbiphenyl in the nematic phase. Hence, these molecules can be suitably used as nonlinear optical materials in PMMA matrix for device applications.
{"title":"Effect of polymer host on third order nonlinear optical properties of newly synthesized organic liquid crystal","authors":"S. Shettigar, G. Umesh, P. Poornesh, Y. Murthy*","doi":"10.1109/ICTONMW.2007.4446920","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446920","url":null,"abstract":"We report the investigation of third order optical nonlinearity of 2,4,6-tri-(p-hyptoyoxylphenyl) pyrilium tetraborate doped PMMA using nanosecond laser pulses at 532 nm wavelength by employing Z-Scan technique. To see the effect of polymer host, the results have been compared with the pure dopant. The material shows a large negative nonlinearity with real and imaginary parts of chi(3) are - 3.31times10-14 esu and 0.73times10-14 esu respectively. Excited state absorption cross-section is found to be 3.41times10-48 cm4.s/photon in PMMA host. The magnitude of third order nonlinear parameters increases when the compound is doped into PMMA matrix because of change in the conformation of chain geometry as a result of charge transfer processes. The values are comparable with a best known nonlinear liquid crystal molecule namely, 4-cyano-4'-n-pentylbiphenyl in the nematic phase. Hence, these molecules can be suitably used as nonlinear optical materials in PMMA matrix for device applications.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129802314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-11-20DOI: 10.1109/ICTONMW.2007.4446904
M. Leeson, Y. Kavian, W. Ren, E. Hines, M. Naderi
The provision of acceptable service in the presence of failures and attacks is a major issue in the design of next generation dense wavelength division multiplexing (DWDM) networks. Survivability is provided by the establishment of redundant lightpaths for each connection request to protect the primary lightpaths. This paper presents a genetic algorithm (GA) solver for the routing and wavelength assignment problem with working and spare lightpaths. The proposed approach has been evaluated on both dedicated path protection and shared path protection. Simulation results show that the GA method is efficient and able to design DWDM survivable real-world optical mesh networks.
{"title":"Survivable wavelength-routed optical network design using genetic algorithms","authors":"M. Leeson, Y. Kavian, W. Ren, E. Hines, M. Naderi","doi":"10.1109/ICTONMW.2007.4446904","DOIUrl":"https://doi.org/10.1109/ICTONMW.2007.4446904","url":null,"abstract":"The provision of acceptable service in the presence of failures and attacks is a major issue in the design of next generation dense wavelength division multiplexing (DWDM) networks. Survivability is provided by the establishment of redundant lightpaths for each connection request to protect the primary lightpaths. This paper presents a genetic algorithm (GA) solver for the routing and wavelength assignment problem with working and spare lightpaths. The proposed approach has been evaluated on both dedicated path protection and shared path protection. Simulation results show that the GA method is efficient and able to design DWDM survivable real-world optical mesh networks.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132487125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1109/ictonmw.2007.4446909
S. Couris
The investigation of the nonlinear optical response of various Au nanostructures has been recently accomplished in our laboratory and some selected results concerning the nonlinear optical properties of these nanostructures will be presented and discussed. In particular, the third-order nonlinear optical response of nanometer thick Au films and Au nano-island films, both deposited on transparent dielectric substrates, are going to be presented and discussed. In addition, the nonlinear optical response of Au nano-clusters encapsulated in block copolymer micelles will be also presented and compared with the other nanostructures. In all cases, the influence of the morphological characteristics of these structures on the nonlinear optical response will be discussed.
{"title":"Nonlinear optical properties of some Au nanostructures","authors":"S. Couris","doi":"10.1109/ictonmw.2007.4446909","DOIUrl":"https://doi.org/10.1109/ictonmw.2007.4446909","url":null,"abstract":"The investigation of the nonlinear optical response of various Au nanostructures has been recently accomplished in our laboratory and some selected results concerning the nonlinear optical properties of these nanostructures will be presented and discussed. In particular, the third-order nonlinear optical response of nanometer thick Au films and Au nano-island films, both deposited on transparent dielectric substrates, are going to be presented and discussed. In addition, the nonlinear optical response of Au nano-clusters encapsulated in block copolymer micelles will be also presented and compared with the other nanostructures. In all cases, the influence of the morphological characteristics of these structures on the nonlinear optical response will be discussed.","PeriodicalId":366170,"journal":{"name":"2007 ICTON Mediterranean Winter Conference","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124915145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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