{"title":"Optimization of the photonic crystal fiber by using genetic algorithms","authors":"Jyun-Hong Lu, Chii-Chang Chen","doi":"10.1109/PGC.2012.6458010","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458010","url":null,"abstract":"This paper presents an optimized structure of photonic crystal fiber (PCF) by using genetic algorithms (GAs) and finite different frequency domain method. Our goal is to find a structure having small diffraction angle and good confine property. We also compare the optimal field profile with fitting Bessel function. Although the diffraction angle of Bessel functions is narrower than that in our case, the mode of the optimized structure provides a better confinement. The diffraction angle of optimal PCF can be decreased about 18.2% comparing to the non-optimized case.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128089941","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}
{"title":"Confocal fluorescence spectral imaging technique and its applications to drug development","authors":"A. Feofanov","doi":"10.1109/PGC.2012.6457865","DOIUrl":"https://doi.org/10.1109/PGC.2012.6457865","url":null,"abstract":"A spectral analysis that is widely used to study molecular interactions in solutions can be transferred to cellular and tissue levels and is a basis of a confocal spectral imaging (CSI) technique. The technique is a potent tool to deconvolve overlapping spectra of fluorophores in a specimen, to discriminate weak signals of fluorophores interfering with cellular autofluorescence and to study molecular interactions of drugs within living cells. The CSI technique measures a two-dimensional set of spectra with a three-dimensional spatial resolution from a tissue section or an intact living cell treated with a fluorescent drug and analyzes it in order to: identify and map molecular interactions of the drug; quantify accumulation, localization and retention of the drug in the specimen. Features of the CSI technique are illustrated with our data obtained in the course of development and studies of advanced agents for photodynamic and boron neutron-capture anticancer therapies.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125734788","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}
G. Liang, H. Liang, Ying Zhang, S. Khanna, Lianhe H. Li, A. Davies, E. Linfield, D. F. Lim, C. Tan, S. Yu, H. Liu, Qi Jie Wang
{"title":"Single-mode narrow beam divergence surface-emitting concentric-circular-grating terahertz quantum cascade lasers","authors":"G. Liang, H. Liang, Ying Zhang, S. Khanna, Lianhe H. Li, A. Davies, E. Linfield, D. F. Lim, C. Tan, S. Yu, H. Liu, Qi Jie Wang","doi":"10.1109/PGC.2012.6458023","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458023","url":null,"abstract":"Single-mode surface-emitting terahertz quantum cascade lasers with second-order concentric-circular-gratings are firstly demonstrated. The gratings are designed for single-mode operation and surface emission for efficient and directional optical power out-coupling. The first structure exhibits single-mode operation over the entire dynamic range with a side-mode-suppression-ratio of around 30 dB, and a six-fold rotationally symmetric far-field pattern, while a modified structure demonstrates single-mode operation with an improved beam divergence, whose far-field patteren consists of two lobes, each of which has a beam divergence within 13.5°×7° (full-width at half-maximum, FWHM). In addition, the devices show a peak output power approximately three times higher than in conventional ridge-waveguide lasers of similar size, whilst maintaining similar threshold current densities and maximum operating temperatures.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133282739","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}
{"title":"Structural design of microwave photonic filter based on adaptive genetic algorithm with disturbance operation","authors":"Xiangnong Wu, Ye Yin, J. Zhang, Qiang Ni","doi":"10.1109/PGC.2012.6458093","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458093","url":null,"abstract":"In this paper, the optimization for an FBG array based microwave photonic filter using adaptive genetic algorithm with disturbance operation is proposed, established and studied. In the design we assume that the population size is 50, the maximum number of iterations is 50, the FBG reflectivity is from 0 to 1 and there are six uniform FBGs in the FBG array. The simulation results show that the optimized simulation time can be reduced by half, from 23.5 seconds to 10.8 seconds, compared with that using the traditional genetic algorithm without disturbance. The influences of the number of the FBGs and the range of the tap coefficients of the FBGs are detailed studied. The amplitude frequency response of the MPF will deteriorate when the range of the tap coefficients of the FBGs become smaller. The simulation results for different values of stopband rejections show that the proposed algorithm is feasible.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132575597","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}
{"title":"Experimental demonstration of integrated horizontal Cu-Si3N4-Cu plasmonic waveguide and passive components","authors":"Shiyang Zhu, G. Lo, D. Kwong","doi":"10.1109/PGC.2012.6457949","DOIUrl":"https://doi.org/10.1109/PGC.2012.6457949","url":null,"abstract":"The Si<sub>3</sub>N<sub>4</sub> waveguide offers very low propagation loss and feasibility for three-dimensional photonic integration, but it suffers from large optical mode size (thus low integration density) due to the relatively small refractive index contrast between the Si<sub>3</sub>N<sub>4</sub> core and the SiO<sub>2</sub> cladding. On the other hand, the metal-insulator-metal plasmonic waveguide offers very tight light confinement but it suffers from large propagation loss. In this work, we integrate Cu-Si<sub>3</sub>N<sub>4</sub>-Cu nanoplasmonic waveguides along with various passive components with the conventional Si<sub>3</sub>N<sub>4</sub> waveguides. The Cu-Si<sub>3</sub>N<sub>4</sub>-Cu waveguide exhibits ~0.37-dB/μm propagation loss at telecommunication wavelengths of 1550 nm and ~45% coupling efficiency with the conventional 1-μm-wide S<sub>3</sub>N<sub>4</sub> waveguide through a simple 2-μm-long tapered coupler. Ultracompact 1×2 and 1×4 plasmonic power splitters can split light almost equally with an excess loss of ~3.5 dB and ~1 dB, respectively.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134496156","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}
{"title":"Fabrication of optical fiber gratings through focused ion beam techniques for sensing applications","authors":"Jin Huang, A. Alqahtani, Jaime Viegas, M. Dahlem","doi":"10.1109/PGC.2012.6458009","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458009","url":null,"abstract":"Fiber Bragg gratings and long-period fiber gratings are widely used in optical communication systems and sensing applications. These structures are fabricated by UV-induced index changes along the core of a fiber, with fine control over the grating period and refractive index profile. Further flexibility and control over these structures can be achieved with focused ion beam (FIB) techniques, by fabricating fiber gratings through nano- and micro-machining. These FIB techniques enable the fabrication of gratings with larger index contrast and stronger interaction with environmental samples (ideal for chemical sensing applications). The sub-micron milling of the fibers allows modulating the refractive index with air voids, which can be filled with the sample fluid to be monitored. In this work we explore the design and fabrication of novel fiber grating configurations for sensing applications, inscribed on single-mode fibers using FIB. A single Fabry-Perot cavity is fabricated by milling a hole through the fiber (cladding and core), as well as a long-period grating based on a cascade of partially-etched-through cavities.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127235623","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}
Xiaoxiao Jiang, Qiongchan Gu, Hailong Liu, Linjuan Yang, Jiangtao Lv, G. Si, Hongjun Duan, Zhenhe Ma, Fengwen Wang, N. Xiang
{"title":"Light through nanocrescent arrays","authors":"Xiaoxiao Jiang, Qiongchan Gu, Hailong Liu, Linjuan Yang, Jiangtao Lv, G. Si, Hongjun Duan, Zhenhe Ma, Fengwen Wang, N. Xiang","doi":"10.1109/PGC.2012.6457928","DOIUrl":"https://doi.org/10.1109/PGC.2012.6457928","url":null,"abstract":"In this work, we show the fabrication of nanocrescent arrays with different sizes. We also investigate the optical response of such nanocrescent arrays and perform theoretical calculations. Our approach may find extensive applications in nanophotonics and integrated optics.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127245768","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}
{"title":"Influence of electric field penetration on uniformly doping GaAs photocathode photoelectric emission properties","authors":"L. Ren, B. Chang, Honggang Wang, F. Shi, Hui Guo","doi":"10.1109/PGC.2012.6457987","DOIUrl":"https://doi.org/10.1109/PGC.2012.6457987","url":null,"abstract":"In order to explore the changes of photoelectric emission properties of GaAs material employed in the third generation low light level (LLL) image intensifiers, the influence of electric field penetration on photoelectric emission properties of uniformly doping GaAs photocathode is studied. Based on the establishment of electric field penetration model for uniformly doping GaAs photocathode, the photoelectric trajectories in GaAs photocathode have been calculated in different penetration voltages. The results show that electric field penetration is helpful for enhancing the movement of photoelectrons excitated by the long-wave radiation toward the band bending region (BBR). With increase of electric field penetration, the diffuse circle of photoelectrons reaching the BBR has no obvious difference, and the resolution of GaAs photocathode is improved. The fitted curves of the location distribution of photoelectrons can be expressed by Gaussian formula. The research will be beneficial to promote the development of the LLL night vision technology.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127402352","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}
{"title":"Multi-sensor real-time sensing based on fiber grating array","authors":"Liwei Li, X. Yi, Tamal Shahriar","doi":"10.1109/PGC.2012.6458092","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458092","url":null,"abstract":"A fiber optic sensor array with continuous and real-time sensing capabilities is presented in the paper. The structure includes reflective fiber Bragg gratings with the same wavelength and optical bandwidth in combination with a multi-output optical switch. By turning on the multiple sensor heads sequentially with the synchronization of data acquisition via microcontroller and computer control, real-time measurement and continuous monitoring can be achieved. Experimental results are presented which demonstrate a real-time temperature monitoring with the compensation of the non-linear characteristic of the optical edge filter.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133732267","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}
Irma Saraswati, Nr. Poepawati, Wigajatri P. Retno, El Hadj Dogheche, Didier Decoster, S. Ko, Yong-Hoon Cho, Laurence Considine, D. Pavlidis
{"title":"Investigation of structural, morphological and optical properties of GaN/AlGaN heterostructures on Si","authors":"Irma Saraswati, Nr. Poepawati, Wigajatri P. Retno, El Hadj Dogheche, Didier Decoster, S. Ko, Yong-Hoon Cho, Laurence Considine, D. Pavlidis","doi":"10.1109/PGC.2012.6458110","DOIUrl":"https://doi.org/10.1109/PGC.2012.6458110","url":null,"abstract":"A good justification for gallium nitride on silicone is the potential for integrated optoelectronic circuits and for the low cost bring by growth of GaN on a large size wafers. Actually, the application interest for GaN/Si is power electronics. This work focused on the optimization of the growth process for GaN/Si and the relation between the structure and the optical properties. Using the guided wave prism coupling technique, we have fully established the index dispersion of GaN at room temperature and its temperature dependence in the wavelength range 0.4 to 1.5μm. We report a slightly low temperature dependence. Results demonstrated excellent waveguide properties of GaN on silicon with optical propagation loss below 1dB/cm. We compared trhe results on Si with those on sapphire. This opens a real opportunity of future device using this technology.","PeriodicalId":158783,"journal":{"name":"2012 Photonics Global Conference (PGC)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114338813","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}