[1]红外动目标识别跟踪系统的dsp+fpga实现




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Nonlinear Optics


231

Author(s): Ganeev, RA (Ganeev, R. A.); Suzuki, M (Suzuki, M.); Baba, M (Baba, M.); Ichihara, M (Ichihara, M.); Kuroda, H (Kuroda, H.)

Title: Low- and high-order nonlinear optical properties of BaTiO3 and SrTiO3 nanoparticles

Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 25 (3): 325-333 MAR 2008

Abstract:

We present the studies of the third- and higher-order nonlinear optical processes in barium titanate (BaTiO3) and strontium titanate (SrTiO3) nanoparticles. We measured the nonlinear refractive indices and nonlinear absorption coefficients of the BaTiO3 and SrTiO3 nanoparticles dissolved in ethylene glycol using the 790 nm fs and ps pulses. The high-order harmonic generation up to the 39th order was achieved in the BaTiO3 and SrTiO3 nanoparticles-contained plumes when the femtosecond radiation propagated through the preformed plasma. The 1 X 10(-6) and 4 X 10(-6) high-order harmonic efficiencies at the plateau region were achieved in the cases of the BaTiO3 and SrTiO3 nanoparticles-contained plasmas. (C) 2008 Optical Society of America.


Addresses: Univ Tokyo, Inst Solid State Phys, Chiba 2778581, Japan

Sci Assoc Akadempribor, Tashkent 100125, Uzbekistan

Reprint Address: GANEEV, RA, UNIV TOKYO, INST SOLID STATE PHYS, 5-1-5 KASHIWANOHA, CHIBA 2778581, JAPAN

Author's E-mail: rashid_ganeev@mail.ru

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232


Author(s): Ray, PC (Ray, Paresh C.); Bonifassi, P (Bonifassi, P.); Leszczynski, J (Leszczynski, J.)

Title: Influence of the central metal ion on nonlinear optical and two-photon absorption properties of push-pull transition metal porphyrins

Source: JOURNAL OF PHYSICAL CHEMISTRY A, 112 (13): 2870-2879 APR 3 2008

Abstract:

We present a quantum-chemical analysis of the central metal ion's effect on first hyperpolarizabilities and two-photon absorption (TPA) cross sections at the infrared region of a series of push-pull porphyrins whose synthesis and NLO properties have been reported earlier (J. Am. Chem. Soc. 2005, 127, 9710). The molecular geometries are obtained via the B3LYP/6-31G(d,p) level optimization including SCRF/PCM approach, and the NLO and TPA properties are calculated with the ZINDO/CV method including solvent effects. It is found that the CT transition between the metal ion's d orbital and the macrocycle 7 orbitals plays an important role on NLO and TPA properties of metal porphyrins. Our data suggest a new approach to enhance TPA properties of porphyrin materials. We also present a quantum-chemical analysis on porphyrin dimers and trimers to understand the relationship between structural and collective NLO properties. It has been observed that beta values can be improved about an order of magnitude and TPA properties can be enhanced by 2 orders of magnitude by the formation of a trimer. The importance of our results with respect to the design of photonic and photodynamic therapy materials have been discussed.
Addresses: Jackson State Univ, Dept Chem, Jackson, MS 39217 USA

Reprint Address: RAY, PC, JACKSON STATE UNIV, DEPT CHEM, JACKSON, MS 39217 USA

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233


Author(s): Grapinet, M (Grapinet, Melanie); Udaltsov, V (Udaltsov, Vladimir); Jacquot, M (Jacquot, Maxime); Lacourt, PA (Lacourt, Pierre-Ambroise); Dudley, JM (Dudley, John M.); Larger, L (Larger, Laurent)

Title: Experimental chaotic map generated by picosecond laser pulse-seeded electro-optic nonlinear delay dynamics - art. no. 013110

Source: CHAOS, 18 (1): 13110-13110 MAR 2008

Abstract:

We describe experimental studies of the dynamical behavior of a recently proposed electro-optic discrete time nonlinear delay oscillator. With appropriate choice of the oscillator loop parameters and external forcing of the dynamics using a pulsed laser source, the system allows for the physical realization of a high dimensional mathematical nonlinear mapping. The dynamical features observed with this new class of discrete time delay oscillator differ significantly from those observed with similar continuous time nonlinear delay feedback oscillators and reveal the intrinsic discrete time nature of the dynamics. We also discuss specific applications to chaos communications using regularly clocked binary data. (C) 2008 American Institute of Physics.
Addresses: Univ Franche Comte, FEMTO ST Inst, CNRS, UMR 6174,Opt Dept, F-25030 Besancon, France

SI Vavilov State Opt Inst, St Petersburg 199034, Russia

Inst Laser Phys, St Petersburg 199034, Russia

Reprint Address: LARGER, L, UNIV FRANCHE COMTE, FEMTO ST INST, CNRS, UMR 6174,OPT DEPT, 16 ROUTE GRAY, F-25030 BESANCON, FRANCE

Author's E-mail: laurent.larger@univ-fcomte.fr

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234

Author(s): Kiran, AJ (Kiran, A. John); Kim, HC (Kim, H. C.); Kim, K (Kim, K.); Rotermund, F (Rotermund, F.); Ravindra, HJ (Ravindra, H. J.); Dharmaprakash, SM (Dharmaprakash, S. M.); Lim, H (Lim, H.)



Title: Superior characteristics of organic chalcone single crystals as efficient nonlinear optical material - art. no. 113307

Source: APPLIED PHYSICS LETTERS, 92 (11): 13307-13307 MAR 17 2008

Abstract:

High-quality biaxial single crystals of chalcone derivatives were grown by solution growth technique. Their molecular structures were designed to possess large second-order nonlinearities by choosing proper donor/acceptor groups while retaining a high transparency in the visible and infrared spectral regions. The second-order nonlinear optical coefficients, determined by applying the Maker fringe technique, were found to be much larger than those of LiB3O5, KTiOPO4, KH2PO4, and urea. The advantages, such as easy synthesis and crystal growth, low cutoff wavelength (< 450 nm), large optical nonlinearity, and high damage threshold (>7.2 GW/cm(2)), make these organic crystals promising for efficient frequency doubling. (C) 2008 American Institute of Physics.


Addresses: Ajou Univ, Div Energy Syst Res, Suwon 443749, South Korea

Mangalore Univ, Dept Phys, Mangalagangothri 574199, Karnataka, India

Ajou Univ, Dept Elect Engn, Suwon 443749, South Korea

Reprint Address: KIRAN, AJ, AJOU UNIV, DIV ENERGY SYST RES, SUWON 443749, SOUTH KOREA

Author's E-mail: rotermun@ajou.ac.kr

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235

Author(s): Liu, DJ (Liu Da-Jun); He, XQ (He Xing-Quan); Gao, ZG (Gao Zheng-Guo); Duan, Q (Duan Qian); Zhou, FG (Zhou Fen-Guo)



Title: Nonlinear and optical limiting properties of tetra tert-butylnaphthalocyanine lead

Source: ACTA CHIMICA SINICA, 66 (5): 563-566 MAR 14 2008

Abstract:

The compound of tetra tert-butylnaphthalocyanine lead was synthesized. The structure of the compound was characterized by means of elemental analysis, infrared spectrum and hydrogen nuclear magnetic resonance spectrum. A frequency-doubled Q switched Nd:YAG pulse laser system with ns/ps laser pulse was used for studying the nonlinear and optical limiting properties of the synthesized compound at the wavelength of 532 nm. The nonlinear refracting index, n(2), and third-order nonlinear polarizability, chi((3)) were determined to be 2.54 X 10(-11) and 9.51 X 10(-12) esu, respectively. The molecular polarizability of the compound gamma' was calculated to be 3.3 X 10(-29) esu. When visible light transmittance was 69%, the limiting threshold value was 1522 mJ/cm(2), the clamp value was 553 mJ/cm(2), and the ratio of absorption sectional area of effective excited state to that of ground state was 3.16.


Addresses: Chanchun Univ Sci & Technol, Coll Chem & Environm Engn, Changchun 130022, Peoples R China

Reprint Address: LIU, DJ, CHANCHUN UNIV SCI & TECHNOL, COLL CHEM & ENVIRONM ENGN, CHANGCHUN 130022, PEOPLES R CHINA

Author's E-mail: ldj478@sohu.com

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236

Author(s): Sakhnovich, A (Sakhnovich, Alexander)



Title: Weyl functions, the inverse problem and special solutions for the system auxiliary to the nonlinear optics equation - art. no. 025026

Source: INVERSE PROBLEMS, 24 (2): 25026-25026 APR 2008

Abstract:

A Borg-Marchenko-type uniqueness theorem ( in terms of the Weyl function) is obtained here for the system auxiliary to the N-wave equation. A procedure to solve the inverse problem is used for this purpose. The asymptotic condition on the Weyl function, under which the inverse problem is uniquely solvable, is completed by a new and simple sufficient condition on the potential, which implies this asymptotic condition. The evolution of the Weyl function is discussed and the solution of an initial-boundary-value problem for the N-wave equation follows. Explicit solutions of an inverse problem are obtained. The system with a shifted argument is treated.


Reprint Address: SAKHNOVICH, A, UNIV VIENNA, FAK MATH, NORDBERGSTR 15, A-1090 VIENNA, AUSTRIA

Author's E-mail: al_sakhnov@yahoo.com

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237


Author(s): Xu, T (Xu, Tao); Li, J (Li, Juan); Zhang, HQ (Zhang, Hai-Qiang); Zhang, YX (Zhang, Ya-Xing); Hu, W (Hu, Wei); Gao, YT (Gao, Yi-Tian); Tian, B (Tian, Bo)

Title: Integrable aspects and applications of a generalized inhomogeneous N-coupled nonlinear Schrodinger system in plasmas and optical fibers via symbolic computation

Source: PHYSICS LETTERS A, 372 (12): 1990-2001 MAR 17 2008

Abstract:

For describing the general behavior of N fields propagating in inhomogeneous plasmas and optical fibers, a generalized N-coupled nonlinear Schrodinger system is investigated with symbolic computation in this Letter. When the coefficient functions obey the Painleve-integrable conditions, the (N + 1) x (N + 1) nonisospectral Lax pair associated with such a model is derived by means of the Ablowitz-Kaup-Newell-Segur formalism. Furthermore, the Darboux transformation is constructed so that it becomes exercisable to generate the multi-soliton solutions in a recursive manner. Through the graphical analysis of some exact analytic one- and two-soliton solutions, our discussions are focused on the envelope soliton excitation in time-dependent inhomogeneous plasmas and the optical pulse propagation with the constant (or distance-related) fiber gain/loss and phase modulation. (c) 2007 Elsevier B.V. All rights reserved.
Addresses: Beijing Univ Posts & Telecommun, Sch Sci, Beijing 100876, Peoples R China

Beijing Univ Aeronaut & Astronaut, Dept Math, Beijing 100083, Peoples R China

Beijing Univ Aeronaut & Astronaut, LMIB, Beijing 100083, Peoples R China

Beijing Univ Aeronaut & Astronaut, Minist Educ, Key Lab Fluid Mech, Beijing 100083, Peoples R China

Beijing Univ Aeronaut & Astronaut, Natl Lab Computat Fluid Dynam, Beijing 100083, Peoples R China

Beijing Univ Aeronaut & Astronaut, State Key Lab Software Dev Environm, Beijing 100083, Peoples R China

Beijing Univ Posts & Telecommun, Minist Educ, Key Lab Opt Commun & Lightwave Technol, Beijing 100876, Peoples R China

Reprint Address: TIAN, B, BEIJING UNIV POSTS & TELECOMMUN, SCH SCI, POB 122, BEIJING 100876, PEOPLES R CHINA

Author's E-mail: gaoyt@public.bta.net.cn

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238

Author(s): Deng, Y (Deng, Yan); Sun, YY (Sun, Youyi); Wang, P (Wang, Pei); Zhang, DG (Zhang, Douguo); Ming, H (Ming, Hai); Zhang, QJ (Zhang, Qijing)



Title: In situ synthesis and nonlinear optical properties of Ag nanocomposite polymer films

Source: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, 40 (4): 911-914 FEB 2008

Abstract:

The Ag nanocomposite polymer films were prepared by in situ synthesis. The presence of silver nanoparticles is confirmed by transmission electron microscopy (TEM) and electron diffraction (ED), which show that the particles' average sizes are about 10 nm and the particles can be dispersed in a polymer matrix. Nonlinear optical measurements, performed by Z-scan techniques, are further presented. The addition of silver nanoparticles to the polymer film leads to the enhancement of nonlinear optical properties. The nonlinear refractive index and nonlinear absorption coefficient are measured to be 3.708 x 10(-11) m(2)/W and 1.221 x 10(-8) m/W, respectively. The enhanced nonlinear optical properties are due to the surface plasmon resonance of silver nanoparticles. The Ag nonlinear polymer film shows promise for practical use in all optical devices. (C) 2007 Elsevier B.V. All rights reserved.


Addresses: Univ Sci & Technol China, Dept Phys, Anhua 230026, Hefei, Peoples R China

Univ Sci & Technol China, Dept Polymer Sci & Engn, Hefei 230026, Peoples R China

N Univ China, Coll Mat Sci & Engn, Taiyuan 030051, Peoples R China

Reprint Address: DENG, Y, UNIV SCI & TECHNOL CHINA, DEPT PHYS, ANHUA 230026, HEFEI, PEOPLES R CHINA

Author's E-mail: dyz2000@mail.ustc.edu.cn

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239

Author(s): Li, HM (Li Hua-Mei)



Title: Exact self-similar solitary waves and collisions in nonlinear optical media

Source: CHINESE PHYSICS B, 17 (3): 759-763 MAR 2008

Abstract:

This paper analyses bright and dark spatial self-similar waves propagation and collision in graded-index nonlinear waveguide amplifiers with self-focusing and self-defocusing Kerr nonlinearities. It finds an appropriate transformation for the first time such that the nonlinear Schrodinger equation (NLSE) with varying coefficients transform into standard NLSE. It obtains one-solitonlike, two-solitonlike and multi-solitonlike self-similar wave solutions by using the transformation. Furthermore, it analyses the features of the self-similar waves and their collisions.


Addresses: Zhejiang Normal Univ, Dept Phys, Jinhua 321004, Peoples R China

Reprint Address: LI, HM, ZHEJIANG NORMAL UNIV, DEPT PHYS, JINHUA 321004, PEOPLES R CHINA

Author's E-mail: lihuamei@zjnu.cn

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240

Author(s): Xiao, L (Xiao Li); Zhang, W (Zhang Wei); Huang, YD (Huang Yi-Dong); Peng, JD (Peng Jiang-De)



Title: Polarization dependent dispersion and its impact on optical parametric process in high nonlinear microstructure fibre

Source: CHINESE PHYSICS B, 17 (3): 995-999 MAR 2008

Abstract:

High nonlinear microstructure fibre (HNMF) is preferred in nonlinear fibre optics, especially in the applications of optical parametric effects, due to its high optical nonlinear coefficient. However, polarization dependent dispersion will impact the nonlinear optical parametric process in HNMFs. In this paper, modulation instability (MI) method is used to measure the polarization dependent dispersion of a piece of commercial HNMF, including the group velocity dispersion, the dispersion slope, the fourth-order dispersion and group birefringence. It also experimentally demonstrates the impact of the polarization dependent dispersion on the continuous wave supercontinuum (SC) generation. On one axis MI sidebands with symmetric frequency detunings are generated, while on the other axis with larger MI frequency detuning, SC is generated by soliton self-frequency shift.


Addresses: Tsinghua Univ, Dept Elect Engn, Beijing 100084, Peoples R China

Reprint Address: XIAO, L, TSINGHUA UNIV, DEPT ELECT ENGN, BEIJING 100084, PEOPLES R CHINA

Author's E-mail: xiaoli99@mails.thu.edu.cn

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241

Author(s): Feng, CF (Feng Chuan-Fen); Wu, J (Wu Jian); Zhang, JY (Zhang Jun-Yi); Xu, K (Xu Kun); Lin, JT (Lin Jin-Tong)



Title: Towards 640 Gbit/s wavelength conversion based on nonlinear polarization rotation in a semiconductor optical amplifier

Source: CHINESE PHYSICS B, 17 (3): 1000-1007 MAR 2008

Abstract:

Taking into account ultra-fast carrier dynamics, this paper models 640 Gbit/s wavelength conversion scheme based on nonlinear polarization rotation (NPR) in a single semiconductor optical amplifier (SOA) and investigates the performance of this kind of wavelength conversion scheme in detail. In this model, two carrier temperature equations are introduced to substitute two energy density equations, which reduce the complexity of calculation in comparison with the previous model. The temporary gain and phase shift dynamics induced by ultra-short optical pulses are numerically simulated and the simulated results are qualitatively in good agreement with reported experimental results. Simulated results show that non-inverted and inverted 640 Gbit/s wavelength conversions based on NPR are achieved with clear open eye diagrams. To further investigate the performance of the non-inverted wavelength conversion scheme, the dependence of output extinction ratio (ER) on some key parameters used in simulation is illustrated. Furthermore, simulated analyses show that high performance non-inverted wavelength conversion based on NPR can be achieved by using a red-shifted filtering scheme.


Addresses: Beijing Univ Posts & Telecommun, Key Lab Opt Commun & Lightware Technol MOE, Beijing 100876, Peoples R China

Reprint Address: FENG, CF, BEIJING UNIV POSTS & TELECOMMUN, KEY LAB OPT COMMUN & LIGHTWARE TECHNOL MOE, BEIJING 100876, PEOPLES R CHINA

Author's E-mail: fengchuanfen@gmail.com

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242

Author(s): Venkatram, N (Venkatram, N.); Rao, DN (Rao, D. Narayana); Giribabu, L (Giribabu, L.); Rao, SV (Rao, S. Venugopal)



Title: Nonlinear optical and optical limiting studies of alkoxy phthalocyanines in solutions studied at 532 nm with nanosecond pulse excitation

Source: APPLIED PHYSICS B-LASERS AND OPTICS, 91 (1): 149-156 APR 2008

Abstract:

We report our results on the nonlinear optical and optical limiting properties of two alkoxy phthalocyanines namely 2,3,9,10,16,17,23,24-octakis-(heptyloxy) phthalocyanine and 2,3,9,10,16,17,23,24-octakis-(heptyloxy) phthalocyanine zinc(II) studied at a wavelength of 532 nm using 6 ns pulses. Using the standard Z-scan technique we observed that both the phthalocyanines exhibited negative nonlinearity as revealed by the signature of closed aperture data. The magnitude of the nonlinear refractive index n(2) evaluated from the closed aperture data was \ similar to 1.61 x 10(-11) cm(2)/ Wfor the free-base phthalocyanine and similar to 1.56 x 10(-11) cm(2)/ Wfor the metallic phthalocyanine. Open aperture Z-scan data indicates strong nonlinear absorption in both the phthalocyanines with measured nonlinear coefficients of similar to 1650 cm/ GW and similar to 1850 cm/GW respectively. We also report optical limiting properties of these phthalocyanines with limiting thresholds (I-1/2) of similar to 0.5 J/cm(2). Our studies suggest that these phthalocyanines are one of the best molecules for nonlinear optical applications studied recently.


Addresses: Univ Hyderabad, Sch Phys, ACRHEM, Hyderabad 500046, Andhra Pradesh, India

Indian Inst Chem Technol, Inorgan & Phys Chem Div, Nanomat Lab, Hyderabad 500007, Andhra Pradesh, India

Indian Inst Technol Guwahati, Dept Phys, Gauhati 781039, Assam, India

Reprint Address: RAO, SV, UNIV HYDERABAD, SCH PHYS, ACRHEM, HYDERABAD 500046, ANDHRA PRADESH, INDIA

Author's E-mail: svrsp@uohyd.enret.in

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243

Author(s): Reshak, AH (Reshak, Ali Hussain); Auluck, S (Auluck, S.); Kityk, IV (Kityk, I. V.)



Title: Optical susceptibilities of Na3La9O3(BO3)(8), ternary oxyborate nonlinear single crystal: theory and experiment - art. no. 145209

Source: JOURNAL OF PHYSICS-CONDENSED MATTER, 20 (14): 45209-45209 APR 9 2008

Abstract:

Experimental and theoretical simulations of linear and nonlinear optical susceptibilities of the novel Na3La9O3(BO3)(8), a ternary oxyborate nonlinear single crystal, are reported here. The calculations were based on one of the most accurate methods for the computation of the linear and nonlinear optical susceptibilities of solids within density functional theory. Our calculations show that the edges of optical absorption for epsilon 1/2(omega) and epsilon(parallel to)(2)(omega) are located at 5.2 eV, in good agreement with our measurements. The anisotropy is in good agreement with the theoretical data. The same is true for the birefringence. We found that our calculated and measured refractive indices are in good agreement with those obtained by previous measurements. The imaginary and real parts of the second order second harmonic generation (SHG) susceptibility chi((2))(222)(omega) and chi((2))(112)(omega) were evaluated. Our calculation shows that chi((2))(112)(omega) is the dominant component, which shows the largest total Re chi((2))(ijk)(0) value (2.3 pmV(-1)) compared to chi((2))(222)(omega). This value shows very good agreement with experimental data (2.0 pmV(-1)) obtained by previous measurements and our measurements. One specific feature of the investigated crystals consists in substantial anisotropy of their properties, which plays a crucial role in the observed experimental dependences.

These crystals possess very highly nonlinear optical properties. The coefficient of the SHG is about three to five times larger than that of KH2PO4 (KDP).
Addresses: Univ S Bohemia, Inst Phys Biol, Nove Hrady 37333, Czech Republic

Acad Sci Czech Republic, Inst Syst Biol & Ecol, Nove Hrady 37333, Czech Republic

Indian Inst Technol, Dept Phys, Kanpur 208016, Uttar Pradesh, India

J Dlugosz Univ Czestochowa, Inst Phys, Czestochowa, Poland

Silesian Tech Univ, Dept Chem, PL-44100 Gliwice, Poland

Reprint Address: RESHAK, AH, UNIV S BOHEMIA, INST PHYS BIOL, NOVE HRADY 37333, CZECH REPUBLIC

Author's E-mail: maalidph@yahoo.co.uk

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244

Author(s): Zhang, L (Zhang Li)



Title: Studies on linear and nonlinear intersubband optical absorptions in a wurtzite AlGaN/GaN coupling quantum well

Source: COMMUNICATIONS IN THEORETICAL PHYSICS, 49 (3): 786-790 MAR 15 2008

Abstract:

Based on the density matrix approach and iterative procedure, a detailed procedure for the calculation of the linear and nonlinear intersubband optical absorption coefficients is given in wurtzite GaN-based coupling quantum wells (CQWs). The simple analytical formulas for electronic eigenstates and the linear and nonlinear optical absorption coefficients in the systems are also deduced. Numerical result on a typical AlGaN/GaN CQW shows that, the linear and nonlinear optical absorption coefficients sensitively depend on the structural parameters of the CQW system as well as the incident optics beam intensity.


Addresses: Panyu Polytech, Dept Mech & Elect, Panyu 511483, Peoples R China

Reprint Address: ZHANG, L, PANYU POLYTECH, DEPT MECH & ELECT, PANYU 511483, PEOPLES R CHINA

Author's E-mail: zhangli-gz@263.net

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245

Author(s): Wiersma, DS (Wiersma, Diederik Sybolt)



Title: Nonlinear optics: Controlling photons with light

Source: NATURE PHOTONICS, 2 (3): 136-137 MAR 2008

Abstract:

A strongly nonlinear photonic crystal with a wavelength- tunable bandgap could provide the solution to realizing all-optical switches for signal processing.


Addresses: European Lab Nonlinear Spectroscopy, I-50019 Florence, Italy

INFM CNR, I-50019 Florence, Italy

Reprint Address: WIERSMA, DS, EUROPEAN LAB NONLINEAR SPECTROSCOPY, I-50019 FLORENCE, ITALY

Author's E-mail: wiersma@lens.unifi.it


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