2012
2012
-
Record 301 of
Title:3000W CW diode laser cladding system
Author(s):Xiong, Lingling(1); Wang, Min(2); Wang, Xiaobiao(2); Zheng, Yanfang(2); Wu, Di(2); Zhang, Pu(1); Li, Xiaoning(1,3); Wang, Zhenfu(1); Liu, Xingsheng(1,2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8241 Issue: DOI: 10.1117/12.909599 Published: 2012Abstract:Laser cladding has become a useful tool in materials processing for improving the surface properties of the substrate materials, and has been widely used in industry in recent years. In this paper, we study the 3000W CW laser cladding system based on the high power diode lasers. The beam control method is proposed to reduce the collimated beam pointing errors caused during the packaging of the laser stack. At the input current of 84A, the output power and the optical coupling efficiency of this laser cladding system are 3738W and 93.7%, respectively, and at work face the beam spot size is 2.5mm*7.9mm with symmetry intensity distribution. The laser cladding system is also used in cladding the nickel powder onto the iron substrate and the nickel powder can be clothed onto steel plate uniformly. ? 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).Accession Number: 20121014830319 -
Record 302 of
Title:Dispersion-free quantum clock synchronization via fiber link
Author(s):Hou, Fei-Yan(1); Dong, Rui-Fang(1); Quan, Run-Ai(1); Zhang, Yu(1,2); Bai, Yun(1,2); Liu, Tao(1); Zhang, Shou-Gang(1); Zhang, Tong-Yi(3)Source: Advances in Space Research Volume: 50 Issue: 11 DOI: 10.1016/j.asr.2012.07.029 Published: December 1, 2012Abstract:We proposed a fiber-based quantum clock synchronization protocol by employing the dispersion cancellation feature of the frequency anti-correlated entangled source under the quantum interference measurement. It is shown that, the accuracy of the synchronization is mainly dependent on the bandwidth of the frequency entangled biphoton spectrum and on the temperature variation induced fluctuations in both the reference fiber coiling and the fiber link. With this proposal, synchronization between two clocks at a distance of ten kilometers can be implemented with an accuracy below a picosecond. ? 2012 COSPAR. Published by Elsevier Ltd. All rights reserved.Accession Number: 20141517550851 -
Record 303 of
Title:Efficient optical Kerr gate of tellurite glass for acquiring ultrafast fluorescence
Author(s):Zhang, Hang(1); Zhou, Zhiguang(2); Lin, Aoxiang(2); Cheng, Jun(1); Liu, Hui(1); Si, Jinhai(1); Chen, Feng(1); Hou, Xun(1)Source: Journal of Optics Volume: 14 Issue: 6 DOI: 10.1088/2040-8978/14/6/065201 Published: June 2012Abstract:We investigated the ultrafast optical Kerr effect of tellurite glass (Te glass) by the femtosecond time-resolved pumpprobe technique. The Kerr-gated spectra from a chirped supercontinuum (SC) obtained by a Te glass optical Kerr gate (OKG) were of a narrow bandwidth and wide range of transmittance spectra. Time-resolved violet fluorescence of a ZnO thin film with high temporal resolution was measured using the Te glass OKG. Experimental results showed that Te glass was a good candidate for an OKG medium due to its ultrafast response, large transmittance window, and large nonlinear refractive index. ? 2012 IOP Publishing Ltd.Accession Number: 20122015026325 -
Record 304 of
Title:Numerical investigation of an all-optical switch in a graded nonlinear plasmonic grating
Author(s):Wang, Guoxi(1); Lu, Hua(1); Liu, Xueming(1); Gong, Yongkang(1)Source: Nanotechnology Volume: 23 Issue: 44 DOI: 10.1088/0957-4484/23/44/444009 Published: November 9, 2012Abstract:We have proposed and numerically investigated an all-optical switch based on a metal-insulator-metal waveguide with graded nonlinear plasmonic gratings. The influences of grating depth and refractive index of a Kerr nonlinear medium on the transmission of the switch are exactly analyzed by utilizing transmission line theory. The finite-difference time-domain simulation results show that the highly compact structure possesses excellent switch function by tuning the incident electric field intensity. In addition, the simulation results show that this all-optical switch has an ultrawide operating frequency regime and femtosecond-scale response time (130fs). Such a switch can find potential applications for all-optical signal processing and optical communication. ? 2012 IOP Publishing Ltd.Accession Number: 20124415613034 -
Record 305 of
Title:Signal-to-noise ratio of ultrashort pulses enhanced by a fiber Sagnac loop
Author(s):Sun, Qibing(1); Liu, Hongjun(1); Huang, Nan(1); Zhao, Wei(1)Source: Optics and Laser Technology Volume: 44 Issue: 5 DOI: 10.1016/j.optlastec.2011.12.035 Published: July 2012Abstract:A method to enhance the signal-to-noise ratio of ultrashort pulses is presented with picosecond pulses as an example. Numerical simulation and analysis show that the signal-to-noise ratio can be improved by four orders of magnitude using a fiber Sagnac loop with two different fibers. It is also found that there is an optimal length of the fiber for improving the signal-to-noise ratio. This is a useful method for improving the signal-to-noise ratio of the seed light in the chirped pulse amplification (CPA) or optical parametric chirped pulse amplification (OPCPA) systems. ? 2011 Elsevier Ltd. All rights reserved.Accession Number: 20120814786188 -
Record 306 of
Title:Wavelength conversion, time demultiplexing and multicasting based on cross-phase modulation and four-wave mixing in dispersion-flattened highly nonlinear photonic crystal fiber
Author(s):Hui, Zhan-Qiang(1,2); Zhang, Jian-Guo(1,3)Source: Journal of Optics Volume: 14 Issue: 5 DOI: 10.1088/2040-8978/14/5/055402 Published: May 2012Abstract:We propose the use of cross-phase modulation (XPM) and four-wave mixing (FWM) in dispersion-flattened highly nonlinear photonic crystal fibers (HNL-PCFs) to implement the functionalities of wavelength conversion, simultaneous time demultiplexing and wavelength multicasting in optical time-division multiplexing (OTDM) systems. The experiments on wavelength conversion at 80Gbits1and OTDM demultiplexing from 80 to 10Gbits 1 with wavelength multicasting of two channels are successfully demonstrated to validate the proposed scheme, which are carried out by using two segments of dispersion-flattened HNL-PCFs with lengths of 100 and 50m, respectively. Moreover, the bit error rate (BER) performance is also measured. The results show that our designed system can achieve a power penalty of less than 4.6dB for two multicasting channels with a 24nm wavelength span at the BER of 109 when compared with the 10 Gbit/s back-to-back measurement. The proposed system is transparent to bit rate since only an ultrafast third-order nonlinear effect is used. The resulting configuration is compact, robust and reliable, benefiting from the use of dispersion-flattened HNL-PCFs with short lengths. This also makes the proposed system more flexible in the operational wavelengths than those based on dispersion-shifted fibers and traditional highly nonlinear fibers. ? 2012 IOP Publishing Ltd.Accession Number: 20121915012814 -
Record 307 of
Title:Design and characterization of a novel sensor combined imaging and zinc ion sensing
Author(s):Wang, Jian(1,2); Wang, Lili(2)Source: Optical Fiber Technology Volume: 18 Issue: 3 DOI: 10.1016/j.yofte.2012.02.003 Published: May 2012Abstract:A novel fluorescent sensor for Zn(II) detection and imaging is developed by incorporating 1-(2-pyridylazo)-2-naphthol (PAN) and Rhodamine B (RB) in a sol-gel film on an end face of a gradient index (GRIN) lens rod which is tightly connected with an imaging fiber. This technique has high-quality imaging capabilities for observing remote sample while measuring Zn(II). The RB and PAN employed in combination as the indicator for zinc-sensing is much cheaper than that of the other zinc-sensitive fluorescent dyes. The sol is prepared by base catalyzed hydrolysis of tetraethylorthosilicate (TEOS) with the addition of 3-glycidyloxypropyltrimethoxysilane (GLYMO) and 3-aminopropyltriethoxysilane (APTES), which is more suitable for Zn(II) detection. The sensor has the linear range of Zn(II) from 0.1 to 1 mmol/L. Simultaneously, it has the capabilities of real-time imaging with the whole system's resolution of 18.73 line pairs/mm. This bi-functional sensor has potential applications in in situ biosensing and other remote measurements. ? 2012 Elsevier Inc. All rights reserved.Accession Number: 20122115044774 -
Record 308 of
Title:An optical fiber sensor for remote pH sensing and imaging
Author(s):Wang, Jian(1,2); Wang, Lili(2)Source: Applied Spectroscopy Volume: 66 Issue: 3 DOI: 10.1366/11-06492 Published: March 2012Abstract:A fiber-optical probe for pH sensing and real-time imaging is successfully fabricated by connecting a polymer imaging fiber and a gradient index (GRIN) lens rod which was modified with a sensing film. By employing an improved metallographic microscope, an optical system is designed to cooperate with the probe. This novel technique has high-quality imaging capabilities for observing remote samples while measuring pH. The linear range of the probe is pH 1.2-3.5. This technique overcomes the difficulty that high-quality images cannot be obtained when directly using conventional imaging bundles for pH sensing and imaging. As preliminary applications, the corrosion behavior of an iron screw and the reaction process of rust were investigated in buffer solutions of pH 2.0 and 2.9, respectively. The experiment demonstrated that the pH values of the analytes' surface were higher than that of buffer solutions due to the chemical reaction. It provides great potential for applications in optical multifunctional detection, especially in chemical sensing and biosensing. ? 2012 Society for Applied Spectroscopy.Accession Number: 20121614944266 -
Record 309 of
Title:One-dimensional optical materials of microfibers by electrospinning
Author(s):Li, Le(1); Yang, Xinghua(1,2); Yuan, Libo(1)Source: Materials Letters Volume: 66 Issue: 1 DOI: 10.1016/j.matlet.2011.08.068 Published: January 1, 2012Abstract:Optical microfibers of PMMA were fabricated by electrospinning. The fibers with the diameter ranging from 300 nm to 1000 nm were obtained by electrospinning the solutions such as PMMA/DMF, PMMA/DMF/formic acid and PMMA/formic acid. The morphology and the diameter of the fibers were analyzed by scanning electron microscopy (SEM). Results showed that the sidewalls of the fibers were smooth and the diameters were uniform. The light with the wavelength of 488 nm, 532 nm and 650 nm could be launched into the fibers and guide along them. The simulation and experimental results showed that the fibers exhibited excellent optical properties. This method provided an effective and convenient way to fabricate highly uniform micro/nano scale optical waveguide neither using expensive equipments nor involving complex procedures. ? 2011 Elsevier B.V.Accession Number: 20114514505753 -
Record 310 of
Title:All-optical logic gates based on photoinduced anisotropy of bacteriorhodopsin film
Author(s):Han, Junhe(1); Yao, Baoli(2); Gao, Peng(2); Chen, Liju(2); Huang, Mingju(1)Source: Journal of Modern Optics Volume: 59 Issue: 7 DOI: 10.1080/09500340.2011.652202 Published: April 10, 2012Abstract:All-optical logic gates based on photoinduced anisotropy of bacteriorhodopsin (BR) film are proposed. The photoinduced anisotropy in BR film, which arises from the selective absorption of BR molecules to polarized light, can be controlled by changing the amplitudes and polarizations of exiting beams. As a consequence, the polarization of the probe light passing through the BR film can be controlled by the polarization of the exiting beam. Based on this property, a novel scheme of all-optical logic gates, such as AND, OR, XOR and NOT, has been implemented via the pump-probe technique. A theoretical model for the all-optical logic gates is proposed, and the theoretical predictions are demonstrated with the experimental results. ? 2012 Copyright Taylor and Francis Group, LLC.Accession Number: 20121414923160 -
Record 311 of
Title:The resolution estimation of wedge and strip anodes
Author(s):Yang, Hao(1,2); Zhao, Baosheng(1); Liu, Yongan(1); Yan, Qiurong(1); Hu, Huijun(1,2)Source: Review of Scientific Instruments Volume: 83 Issue: 9 DOI: 10.1063/1.4729117 Published: September 2012Abstract:A new resolution estimation method for wedge and strip anode based on the single photon imaging configuration is provided. The limiting resolution estimation equation is deduced theoretically according to the threshold principle. The relation between the charge cloud and the covered electrodes is discussed, and the equivalent diameter number is calculated. The resolution equation for the position deviation amplitude or FWHM is provided if noise exists. The relation between the position deviation amplitude and the total charge deviation amplitudes is discussed. The constancy of the position deviation amplitudes versus positions is provided. The results calculated from these equations are discussed. According to the equations, it is indicated that the spatial resolution is affected by the detection system configuration and noise. These conclusions may be useful for the designing and performance improvement of future photon imagers. ? 2012 American Institute of Physics.Accession Number: 20124115540712 -
Record 312 of
Title:Threshold characteristics analysis of one-end-pumped Yb3-doped gain-guided and index-antiguided fiber laser
Author(s):Qu, Yibin(1); Zhu, Yonggang(2); Zhou, Enyu(2); Wei, Wei(1,2); Peng, Bo(1,2)Source: Optics and Laser Technology Volume: 44 Issue: 3 DOI: 10.1016/j.optlastec.2011.09.014 Published: April 2012Abstract:An exact analytical expression of the threshold pump power for the one-end-pumped Yb3-doped gain-guided and index-antiguided (GGIAG) fiber laser has been obtained by solving the improved rate equations (REs) with the additional leakage losses. The effects of Yb3 concentration, fiber length, core radius and mirror reflectivity on the threshold pump power are discussed. After optimizing, the results show that the laser threshold of GGIAG fiber laser can be greatly reduced while maintaining single mode oscillation. Compared to the numerical methods, the analytical expression has easy calculation and distinct results. ? 2011 Elsevier Ltd. All rights reserved.Accession Number: 20114514500176