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Journal of the Optical Society of America B

Journal of the Optical Society of America B



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Early Posting

Accepted papers to appear in an upcoming issue

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Articles 1 to 20 of 25 Next Page >>


Efficient numerical method for direct Zakharov - Shabat scattering problem

  • David Shapiro, Leonid Frumin, Oleg Belai, and Evgeny Podivilov
  • received 10/28/2014; accepted 12/15/2014; posted 12/15/2014; Doc. ID 225812
  • [full text: PDF (324) KB)]
  • Abstract: New method to solve the direct Zakharov - Shabat scattering problem is proposed based on solution of coupled Gel'fand - Levitan - Marchenko integral equations. Speedup of computation is achieved by using the Toeplitz symmetry of the matrix and ``inner bordering' procedure. New algorithm was tested on exactly solvable potential. It is shown that suggested algorithm significantly surpasses the traditional transfer matrix method in efficiency.

Keywords (OCIS):

  • (000.4430) General : Numerical approximation and analysis
  • (060.1660) Fiber optics and optical communications : Coherent communications
  • (190.4370) Nonlinear optics : Nonlinear optics, fibers
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Comment on “Elliptic cylindrical pseudo-optical black hole for omnidirectional light absorber”

  • Alexander Kildishev, Ludmila Prokopeva, and Evgenii Narimanov
  • received 11/20/2014; accepted 12/09/2014; posted 12/15/2014; Doc. ID 228243
  • [full text: PDF (2995) KB)]
  • Abstract: We prove that Lee’s et al. theoretical analysis and a final formula for ray trajectories in an elliptic cylindrical optical ‘black hole’ are incorrect. By utilizing a full wave finite-element simulation we show that a non-paraxial Gaussian beam does not follow a trajectory obtained using their recipe.

Keywords (OCIS):

  • (260.0260) Physical optics : Physical optics
  • (350.6980) Other areas of optics : Transforms
  • (080.4295) Geometric optics : Nonimaging optical systems
  • (080.5692) Geometric optics : Ray trajectories in inhomogeneous media
  • (260.2710) Physical optics : Inhomogeneous optical media

Vortex Beams with Strong Longitudinally Polarized Magnetic Field and their Generation by Using Metasurfaces

  • Mehdi Veysi, Caner Guclu, and Filippo Capolino
  • received 09/19/2014; accepted 12/09/2014; posted 12/15/2014; Doc. ID 223477
  • [full text: PDF (1356) KB)]
  • Abstract: A novel method of generation and synthesis of azimuthally E-polarized vortex beams is presented. Along the axis of propagation such beams have a strong longitudinally polarized magnetic field where ideally there is no electric field. We show how these beams can be constructed through the interference of Laguerre-Gaussian beams carrying orbital angular momentum. As an example, we present a metasurface made of double-split ring slot pairs and report a good agreement between simulated and analytical results. Both a high magnetic-to-electric-field contrast ratio and a magnetic field enhancement are achieved. We also investigate the metasurface physical constraints to convert a linearly polarized beam into an azimuthally E-polarized beam and characterize the performance of magnetic field enhancement and electric field suppression of a realistic metasurface. These findings are potentially useful for novel optical spectroscopy related to magnetic dipolar transitions and for optical manipulation of particles with spin and orbital angular momentum.

Keywords (OCIS):

  • (260.2110) Physical optics : Electromagnetic optics
  • (250.5403) Optoelectronics : Plasmonics
  • (050.6624) Diffraction and gratings : Subwavelength structures

Nonlinear silicon photonics analyzed with the moment method

  • Simon Lefrancois, Chad Husko, Benjamin Eggleton, and Andrea Blanco-Redondo
  • received 10/06/2014; accepted 12/04/2014; posted 12/09/2014; Doc. ID 224238
  • [full text: PDF (377) KB)]
  • Abstract: We apply the moment method to nonlinear pulse propagation in silicon waveguides in the presence of two-photon absorption, free-carrier dispersion and free-carrier absorption. The evolution equations for pulse energy, temporal position, duration, frequency shift and chirp are obtained. We derive analytic expressions for the free-carrier induced blueshift and acceleration and show that they depend only on the pulse peak power. Importantly, these effects are independent of the temporal duration. The moment equations are then numerically solved to provide fast estimates of pulse evolution trends in silicon photonics waveguides. We find that group-velocity and free-carrier dispersion dominate the pulse dynamics in photonic crystal waveguides. In contrast, two-photon and free-carrier absorption dominate the temporal dynamics in silicon nanowires. To our knowledge, this is the first time the moment method is used to provide a concise picture of multiphoton and free-carrier effects in silicon photonics. The treatment and conclusions apply to any semiconductor waveguide dominated by two-photon absorption.

Keywords (OCIS):

  • (130.5990) Integrated optics : Semiconductors
  • (190.4180) Nonlinear optics : Multiphoton processes
  • (190.5530) Nonlinear optics : Pulse propagation and temporal solitons
  • (190.5970) Nonlinear optics : Semiconductor nonlinear optics including MQW

Temperature effects on the main absorption and emission lines of the Pr3+:LiYF4 laser crystal

  • Richard Moncorge, Zhe Liu, Biao Qu, Jean-Louis DOUALAN, Bin Xu, XU Huiying, Zhiping Cai, Alain BRAUD, and Patrice Camy
  • received 11/06/2014; accepted 12/02/2014; posted 12/09/2014; Doc. ID 226204
  • [full text: PDF (452) KB)]
  • Abstract: The widths and the shifts of the most important absorption and emission lines observed in the visible, deep-red and near-infrared spectral domains in the well-known Pr3+-doped LiYF4 laser crystal were measured from 12 to 300 K. The investigated absorption lines are those usually used for laser pumping and located around 444nm (Pr3+ absorption transition 3H4 → 3P2), 469nm (3H4 → 3P1+1I6) and 479nm (3H4 → 3P0), but also around 595 nm (3H4 → 1D2). The emission wavelengths of the investigated luminescence lines are those peaking around 480nm (3P0 → 3H4 transition), 523nm (3P1 → 3H5), 546nm (3P0 → 3H5), 604nm and 607nm (3P0 → 3H6), 640nm (3P0 → 3F2), 698nm (3P0 → 3F3), 721nm (3P0 → 3F4), 907 and 915 nm (3P0 → 1G4). The results are interpreted and successfully described by phonon thermalization processes within emitting energy multiplets and by using the existing linear and quadratic electron-phonon coupling theories.

Keywords (OCIS):

  • (160.3380) Materials : Laser materials
  • (260.3800) Physical optics : Luminescence

Unconventional geometric phase gates between arbitrary two-qubits in a two-dimensional network

  • Zhi-Rong Zhong and Huang XiaoBing
  • received 09/17/2014; accepted 12/01/2014; posted 12/09/2014; Doc. ID 223253
  • [full text: PDF (299) KB)]
  • Abstract: We show that the two-qubits unconventional geometric phase gates between arbitrary pair of distant qubits in a two-dimensional network can be obtained. In the scheme, the off-resonant Raman transitions between two ground states of the trapped atoms which induced by the cavity modes and external field lead to the selective qubit-qubit coupling. As a typical application, this interaction mechanism can be used to realize unconventional geometric phase gates. The advantages of the proposed scheme are that both the atomic spontaneous emission and the cavity decay are effectively suppressed and the interaction time is short, which make the scheme very robust against decoherence.

Keywords (OCIS):

  • (020.5580) Atomic and molecular physics : Quantum electrodynamics
  • (270.0270) Quantum optics : Quantum optics
  • (270.5585) Quantum optics : Quantum information and processing


The Raman pulse duration effect in high-precision atom interferometry gravimeters

  • Xia Li, Cheng-Gang Shao, and Zhong-Kun Hu
  • received 08/04/2014; accepted 11/30/2014; posted 12/09/2014; Doc. ID 220377
  • [full text: PDF (392) KB)]
  • Abstract: For high-precision atom interferometry gravimeters, the effect of the Raman pulse duration will become an appreciable fraction and need to be taken into account. Its influence has been reported considering a homogeneous Earth’s gravitational field in some previous works. In this paper, by decomposing the time evolution operator into two parts, the free evolution part and the interaction part, we develop an approach to study this effect in a realistic situation where the Earth’s gravitational field is inhomogeneous. A mathematic expression for the interferometer phase shift due to the Raman pulse duration effect is obtained, which shows that the Raman pulse duration should be taken into account when the gravimeter reaches a accuracy of 10−10g.

Keywords (OCIS):

  • (000.2690) General : General physics
  • (140.3320) Lasers and laser optics : Laser cooling

Ultraviolet up-conversion by Yb3+ -trimers in CaF2:Yb3+: Cooperative luminescence theory of Ln3+ trimers

  • WP Qin, Cholnam Sin, Guanshi Qin, Changfeng Wu, and Zhenyu Liu
  • received 11/19/2014; accepted 11/29/2014; posted 12/09/2014; Doc. ID 227121
  • [full text: PDF (398) KB)]
  • Abstract: Recently, we observed ultraviolet luminescence in CaF2: Yb3+ under the excitation of 980nm laser. In this paper, cooperative transition theory of three identical lanthanide ions is built through perturbed wave functions of a three-body system with electric multipole interactions. The theoretical results show that d-dd-dq and crystal field effected d-dd-dfd are the main mechanisms in the triple transition processes. The transition rate ratio of Yb3+-dimers and Yb3+-trimers in an Yb3+-hexamer is calculated to be ~1.86×104. This is in reasonable agreement with the experimentally obtained cooperative luminescence intensity ratio of ~2.0×104 in CaF2:Yb3+ under the excitation of 980nm laser.

Keywords (OCIS):

  • (160.4670) Materials : Optical materials
  • (160.5690) Materials : Rare-earth-doped materials
  • (260.3800) Physical optics : Luminescence

Modal method for second harmonic generation in nanostructures

  • Sébastien Héron, Fabrice Pardo, Patrick Bouchon, Jean-Luc Pelouard, and Riad Haidar
  • received 08/04/2014; accepted 11/28/2014; posted 12/09/2014; Doc. ID 220311
  • [full text: PDF (1063) KB)]
  • Abstract: A modal method for the study of second harmonic generation in nanostructures is depicted both for plane waves and focused beam illumination. It is based on the B-Spline Modal Method, and relies on the undepleted pump approximation. The nonlinear polarization induced by an incident plane wave or a focused beam generates a source term at the doubled frequency. The latter is divided into a finite number of sub-sources and the second harmonic field is subsequently computed by integration of these sub-sources contributions.

Keywords (OCIS):

  • (000.4430) General : Numerical approximation and analysis
  • (190.0190) Nonlinear optics : Nonlinear optics
  • (190.2620) Nonlinear optics : Harmonic generation and mixing
  • (050.1755) Diffraction and gratings : Computational electromagnetic methods
  • (050.6624) Diffraction and gratings : Subwavelength structures

Anti-correlated light switching in an optical loop system }

  • Hoonsoo Kang, Bongjune Kim, Woojin Shin, Byoung-Uk Sohn, and Do Kyeong Ko
  • received 09/16/2014; accepted 11/27/2014; posted 12/08/2014; Doc. ID 222963
  • [full text: PDF (676) KB)]
  • Abstract: We have demonstrated anti-correlated light switching between multi-photon transition channels in an optical loop system. Two-colour probe transitions, using rubidium D1 (795 nm) and D2 (780 nm) were included in our loop of an double-Λ system. In anti-correlated light switching, one of two probe transitions is selected as transparent while the other is selected as opaque. In this configuration, we observed completely different behaviour from that seen in a resonant double-Λ system where both probe transmission are transparent or opaque simultaneously. Furthermore, we observed a noise correlation between two-colour probe transmissions when the phase fluctuation of the two probe lasers was converted to the intensity fluctuation. The relative phase fluctuation between the two probe lasers induced an anti-correlation between the intensity noises of two probe lasers in an non-resonant double- system, while a correlation was induced in a resonant double-Λ system. The intensity fluctuation (Correlated or anti-correlated) was easily controlled by detuning the double-Λ system. The noise anti-correlation effect is clearly interpreted as arising from the anti-correlated light switching in an unresonat double-Λ system. This system can be used for noise control as well as optical switch between incoherent two colour laser lights.

Keywords (OCIS):

  • (030.0030) Coherence and statistical optics : Coherence and statistical optics
  • (190.3270) Nonlinear optics : Kerr effect
  • (190.4410) Nonlinear optics : Nonlinear optics, parametric processes
  • (270.1670) Quantum optics : Coherent optical effects

Dynamical generation of dark solitons in spin-orbit-coupled Bose-Einstein condensates

  • Shuai Cao, Chuan-Jia Shan, Dan-Wei Zhang, Xizhou Qin, and Jun Xu
  • received 09/24/2014; accepted 11/25/2014; posted 12/01/2014; Doc. ID 223748
  • [full text: PDF (1832) KB)]
  • Abstract: We numerically investigate the ground state, the Raman-driving dynamics and the nonlinear excitations of a realized spin-orbit-coupled Bose-Einstein condensate in a one-dimensional harmonic trap. Depending on the Raman coupling and the interatomic interactions, three ground-state phases are identified: stripe, plane wave and zero-momentum phases. A narrow parameter regime with coexistence of stripe and zero-momentum or plane wave phases in real space is found. Several sweep progresses across different phases by driving the Raman coupling linearly in time is simulated and the non-equilibrium dynamics of the system in these sweeps are studied. We find kinds of nonlinear excitations, with the particular dark solitons excited in the sweep from the stripe phase to the plane wave or zero-momentum phase within the trap. Moreover, the number and the stability of the dark solitons can be controlled in the driving, which provide a direct and easy way to generate dark solitons and study their dynamics and interaction properties.

Keywords (OCIS):

  • (020.0020) Atomic and molecular physics : Atomic and molecular physics
  • (020.1475) Atomic and molecular physics : Bose-Einstein condensates
  • (190.6135) Nonlinear optics : Spatial solitons

Efficient two-dimensional atom localization via spontaneously generated coherence and incoherent pump

  • Tao Shui, Benli Yu, and Zhiping Wang
  • received 10/14/2014; accepted 11/25/2014; posted 12/01/2014; Doc. ID 224936
  • [full text: PDF (1732) KB)]
  • Abstract: We present a simple scheme of two-dimensional (2D) atom localization controlled by spontaneously generated coherence (SGC) and incoherent pump in a closed Λ-type three-level atomic system. Due to the position-dependent atom-field interaction, the conditional position probability distribution of the atom passing through the standing waves can be directly determined by measuring the phase-sensitive probe absorption-gain spectrum. The role of the SGC and incoherent pump in the precision and spatial resolution of 2D atom localization is studied. It is found that the probability of finding the atom at a particular position in one period of the standing waves can reach 100% via properly adjusting the parameters of the system.

Keywords (OCIS):

  • (020.1670) Atomic and molecular physics : Coherent optical effects
  • (270.0270) Quantum optics : Quantum optics

Optical and electronic properties of undoped La2Be2O5 single crystals in the far ultraviolet energy range

  • Igor Ogorodnikov, Vladimir Pustovarov, and Erbol Ospanbekov
  • received 10/15/2014; accepted 11/24/2014; posted 12/15/2014; Doc. ID 225087
  • [full text: PDF (361) KB)]
  • Abstract: The optical and electronic properties of undoped La2Be2O5 single crystals were determined using low-temperature (T=10K) far ultraviolet (4.9-33eV) synchrotron radiation spectroscopy, optical absorption spectroscopy (T=80 and 320K) and calculations for the dispersions of the optical functions. On the basis of the obtained data we determined the Urbach's formula parameters and the cut-off energy Ec=5.49eV at 80K for the low-energy tail of the host absorption, the bandgap Eg=6.78eV at 10K, the energy threshold for creation of unrelaxed excitons Eex=6.28eV, and other electronic properties.

Keywords (OCIS):

  • (140.3380) Lasers and laser optics : Laser materials
  • (160.2220) Materials : Defect-center materials
  • (160.3220) Materials : Ionic crystals
  • (160.4760) Materials : Optical properties

Noise conversion in Kerr comb RF photonic oscillators

  • Andrey Matsko and Lute Maleki
  • received 10/06/2014; accepted 11/21/2014; posted 12/09/2014; Doc. ID 224303
  • [full text: PDF (414) KB)]
  • Abstract: Transfer of amplitude and phase noise from a continuous wave optical pump to the repetition rate of a Kerr frequency comb is studied theoretically, with focus on generation of spectrally pure radio frequency (RF) signals via demodulation of the frequency comb on a fast photodiode. It is shown that both the high order chromatic dispersion of the resonator spectrum and frequency-dependent quality factor of the resonator modes facilitate the optical-to-RF noise conversion that limits spectral purity of the RF signal.

Keywords (OCIS):

  • (140.4050) Lasers and laser optics : Mode-locked lasers
  • (190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing
  • (230.4910) Optical devices : Oscillators
  • (230.5750) Optical devices : Resonators
  • (140.3948) Lasers and laser optics : Microcavity devices
  • (060.5625) Fiber optics and optical communications : Radio frequency photonics

Modulated photonic band gaps generated by high-order wave mixing

  • Mengqin Gao, Zhiguo Wang, Zakir Ullah, Haixia Chen, Dan Zhang, Yiqi Zhang, and Yanpeng Zhang
  • received 09/23/2014; accepted 11/20/2014; posted 11/20/2014; Doc. ID 223519
  • [full text: PDF (1319) KB)]
  • Abstract: For the first time, we investigate the photonic band gap (PBG) structure through scanning the frequency detunings of the probe field, dressing field and coupling field in the static and moving electromagnetically induced grating (EIG) field. When we scan the frequency detuning of the coupling field, the PBG structure and six wave mixing band gap signal (SWM BGS) appear at the right of the electromagnetically induced transparency (EIT) position. But the PBG structure and SWM BGS appear at the left of the EIT position in case of scanning the probe field frequency detuning. Also, on the condition of scanning the probe field frequency detuning, the SWM BGS appears in two frequency ranges. Moreover, in the moving PBG structure, the nonreciprocity of SWM BGS can be obtained. Furthermore, the intensity, width, location of the SWM BGS can be modulated through changing the frequency detunings and intensities of the probe field, dressing field and coupling field, sample length and the frequency difference of coupling fields in EIG. Such scheme could have potential applications in optical diodes, amplifiers and quantum information processing.

Keywords (OCIS):

  • (190.0190) Nonlinear optics : Nonlinear optics
  • (190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing
  • (300.2570) Spectroscopy : Four-wave mixing
  • (190.4223) Nonlinear optics : Nonlinear wave mixing

Propagation of Airy Gaussian vortex beams through slabs of right-handed materials and left-handed materials

  • Bo Chen, Chidao Chen, Xi Peng, and Dongmei Deng
  • received 09/12/2014; accepted 11/19/2014; posted 11/20/2014; Doc. ID 223054
  • [full text: PDF (4535) KB)]
  • Abstract: By using the method of ABCD matrix, the propagation of Airy Gaussian vortex (AiGV) beams through slabs of right-handed materials (RHMs) and left-handed materials (LHMs) is reported. Based on the Huygens diffraction integral, an approximate analytical propagation equation of AiGV beams is derived. Using numerical simulations, we study the intensity and phase distributions of the AiGV beams in RHMs and LHMs. We find that the optical vortex can destroy the center lobe of the AiGV beams, and the center lobe can reconstruct due to the acceleration of the vortex and the AiGV beam is not consistent. We also investigate the influence of different χ0 on the propagation of the AiGV beams through slabs of RHMs and LHMs, which can control the AiGV beams that tends to an Airy vortex beam with the smaller value, and a Gaussian vortex beam with the larger one. In addition, we elucidate the energy flow and the angular momentum of the AiGV beams.

Keywords (OCIS):

  • (010.3310) Atmospheric and oceanic optics : Laser beam transmission
  • (070.2590) Fourier optics and signal processing : ABCD transforms
  • (350.3618) Other areas of optics : Left-handed materials

Femtosecond laser filamentation with microlens array in air

  • Tingting Xi, Zuoqiang Hao, and Zhijie Zhao
  • received 07/23/2014; accepted 11/17/2014; posted 11/19/2014; Doc. ID 217599
  • [full text: PDF (804) KB)]
  • Abstract: By performing numerical studies, we have shown that during the propagation of femtosecond laser pulses with microlens array in air, the filamentation with an earlier onset can be prolonged almost twice as long as that generated in the case of single lens. The elongation of the filamentation results from the interaction of the regular filaments whose positions correspond to those of the lenslets. The enhancement of supercontinuum is also observed with different ratio as a function of wavelength. More efficient enhancement in the blue side of the spectrum can be obtained by increasing the size of lenslet but at the cost of shortening the filamentation. This process is strongly influenced by the spatiotemporal dynamics of the laser pulse. The microlens array offers a new way to control the filamentation and supercontinuum emission for the long-distance applications of the femtosecond laser pulse.

Keywords (OCIS):

  • (260.5950) Physical optics : Self-focusing
  • (320.2250) Ultrafast optics : Femtosecond phenomena

A thin anisotropic metasurface for simultaneous light focusing and polarization manipulation

  • Mehdi Veysi, Ozdal Boyraz, Filippo Capolino, and Caner Guclu
  • received 08/27/2014; accepted 11/17/2014; posted 12/17/2014; Doc. ID 221794
  • [full text: PDF (1757) KB)]
  • Abstract: The possibility of integration of two important categories of optical components, i.e., circular polarizer and lens, into a thin plasmonic metasurface is examined, for the realistic cases when metal losses cannot be neglected, such as when operating in the visible spectrum, or at infrared when non noble metals are used. Therefore we introduce a metasurface made of nanoantennas that offer enough degrees of freedom to control both amplitude and phase of the reflection coefficient. First a theoretical formulation is developed and then two optimal designs to realize polarizing lenses at mid-infrared frequencies are presented. A two-dimensional array of Y-shaped nanoantennas with polarization dependent and spatially varying phase response offers the possibility of balancing the losses experienced by the x- and y-polarized incident fields and is the basis for such a unique compact polarizing lens.

Keywords (OCIS):

  • (160.3918) Materials : Metamaterials
  • (250.5403) Optoelectronics : Plasmonics
  • (050.6624) Diffraction and gratings : Subwavelength structures

Casimir force between metal and graphene sheets

  • J. Martinez and M. Jalil
  • received 09/10/2014; accepted 11/13/2014; posted 11/20/2014; Doc. ID 222836
  • [full text: PDF (1050) KB)]
  • Abstract: The Casimir force between neutral plates is attractive. For the Casimir force to be really useful one must be able to switch between attraction and repulsion. Exploiting the experimentalist's ability to change the sign of the charge carriers in graphene, we show how the sign of the Fresnel reflection coefficients can be reversed. This gives rise to a Casimir force between a metal sheet and graphene which can be either attracrive or repulsive; we illustrate it for a dielectric cylinder and a graphene sheet.

Keywords (OCIS):

  • (270.5580) Quantum optics : Quantum electrodynamics
  • (160.4236) Materials : Nanomaterials

Mini-Review: Examining Nanophotonics for Integrated Hybrid Systems: A Review of Plasmonics Interconnects and Modulators Using Traditional and Novel Materials

  • Alexandra Boltasseva, Marcello Ferrera, Vladimir Shalaev, and Nathaniel Kinsey
  • received 11/04/2014; accepted 11/12/2014; posted 11/21/2014; Doc. ID 226079
  • [full text: PDF (674) KB)]
  • Abstract: The scaling which has governed the continual increase in density, performance, and efficiency of electronic devices is rapidly reaching its inevitable limitations. In order to sustain the trend of ever increasing bandwidth and performance, new technologies are being considered. Among the many competitors, nanophotonic technologies are especially poised to impact the field of integrated devices. Here, we examine the available technologies, both traditional photonics and plasmonics, with an emphasis on the latter. A summary of the previous advances in the field of nanophotonics (interconnects and modulators), along with more recent works investigating novel and CMOS-compatible materials, are presented with a graphical comparison of their performance. We suggest that nanophotonic technologies offer key advantages for future hybrid electro-photonic devices, where the movement towards new material platforms is a precursor to high-performance, industry-ready devices.

Keywords (OCIS):

  • (130.0130) Integrated optics : Integrated optics
  • (160.3130) Materials : Integrated optics materials
  • (230.4110) Optical devices : Modulators
  • (230.7370) Optical devices : Waveguides
  • (250.5403) Optoelectronics : Plasmonics

Articles 1 to 20 of 25 Next Page >>

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