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ABSTRACT: We investigate the phase squeezing characteristics of a non-degenerate PPLN-PSA. We show that the level of phase squeezing varies with the phase-sensitive-dynamic-range and demonstrate regeneration of a distorted BPSK signal, despite net signal attenuation.
Optical Communication (ECOC), 2011 37th European Conference and Exhibition on; 10/2011
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ABSTRACT: In this paper, we show the recent progress of photonic network technologies for the new generation network (NWGN). The NWGN is based on new design concepts that look beyond the next generation network (NGN) and the Internet. The NWGN will maintain the sustainability of our prosperous civilization and help resolve various social issues and problems by the use of information and communication technologies. In order to realize the NWGN, many novel technologies in the physical layer are required, in addition to technologies in the network control layer. Examples of cutting-edge physical layer technologies required to realize the NWGN include a terabit/s/port or greater ultra-wideband modulation-format-free optical packet switching (OPS) node and an optical packet and circuit integrated node system.
Transparent Optical Networks (ICTON), 2011 13th International Conference on; 07/2011
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ABSTRACT: We developed an optical input module consisting of built-in metal-semiconductor-metal photodiodes (MSM-PDs) and co-planar waveguide transmission lines fabricated on an InP substrate, which is flip-chip bonded with a single-flux-quantum (SFQ) circuit fabricated on a Si substrate. To improve photosensitivity of the MSM-PD for a wavelength above 1530 nm at 4 K, we tested the MSM-PDs made of lattice mismatched In<sub>1-x</sub>Ga<sub>x</sub>As films on InP substrates. By employing In<sub>1-x</sub>Ga<sub>x</sub>As with x=0.44, an apparent reduction of photosensitivity for a wavelength above 1530 nm was suppressed. We also tested newly designed DC/SFQ converters with higher input current sensitivities. The observed current sensitivity was improved to 41 μA, while that in the conventional DC/SFQ converter was 140 μA.
IEEE Transactions on Appiled Superconductivity 07/2011; · 1.04 Impact Factor
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ABSTRACT: We investigate phase-sensitive operation at telecommunication wavelengths in periodically-poled lithium-niobate waveguides, measuring a record phase-dependent dynamic range of 14.5 dB with 5-dB phase-sensitive gain, compared to phase-insensitive operation. We also highlight limitations arising at high pump powers from green light emission and thermal instability which limits performance compared with an ideal theoretical model.
IEEE Photonics Technology Letters 05/2011; · 2.19 Impact Factor
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ABSTRACT: We use high pump power to demonstrate large C-band phase sensitive gain in a periodically-poled lithium-niobate waveguide chip for the first time. We measure a maximum gain/attenuation dynamic range of 9.4 dB with over 3.6 dB phase sensitive gain compared to phase insensitive operation. We also observe phase sensitive gain over a 17 nm bandwidth limited by the booster EDFA gain spectrum.
OptoeElectronics and Communications Conference (OECC), 2010 15th; 08/2010
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ABSTRACT: In this paper, we show the possibility of optical packet switching technology free from data modulation format such as OOK, DPSK, DQPSK, and so on. We also discuss the merit of ultra-wide band optical switching technologies.
Transparent Optical Networks (ICTON), 2010 12th International Conference on; 08/2010
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ABSTRACT: We demonstrate 160 Gb/s wavelength conversion on a PPLN waveguide at room temperature. A maximum power penalty of 2.1 dB for a bit error rate of 10<sup>-9</sup> was achieved over a wavelength range of 29 nm.
Photonics in Switching, 2009. PS '09. International Conference on; 10/2009
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ABSTRACT: In experiments, we demonstrated time-spread 200-Gchip/s 10-Gb/s eight-chip optical binary phase-shift keying code generation and matched filtering based on spectral amplitude and phase control. By using a bandwidth-tunable high-resolution optical spectrum controller that we have previously developed, we were able to control spectral components with 10-GHz resolution in the entire C -band, with rectangular passbands. To demonstrate the application of this spectrum controller to tunable optical label processing, we performed experiments and simulated label generation and processing by controlling the spectrum.
IEEE Photonics Technology Letters 08/2009; · 2.19 Impact Factor
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ABSTRACT: In this paper, we present a review of our recent research activities in tunable wavelength conversion using PPLN waveguides and other applications based on PPLN.
Photonics in Switching, 2006. PS '06. International Conference on; 11/2006
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ABSTRACT: In this paper, we perform analytical characterization of optical pulses propagating through a polarization-sensitive semiconductor optical amplifier (SOA). We derive analytical expressions for the carrier density, gain and phase evolution along the SOA and show how these expressions prove useful in optical signal processing applications. The propagation of counter-propagating pulses as well as pulse streams across SOAs have been analysed and expressions for energy gain have been derived in all these cases. We also show that our analytical results reduce to corresponding results of polarization insensitive SOAs already published. The analytical results are in excellent agreement with detailed numerical simulations done in MATLAB using the NIMROD portal. The analytical calculations lead to significant savings with regard to simulation time and processing capacity requirements. We further prove that the energy gain difference for counter-propagating pulse streams is directly proportional to the difference delay between in them and hence can be used as a measure of the delay difference. This theoretical result agrees well with experimental results
IEEE Journal of Quantum Electronics 11/2006; · 1.88 Impact Factor
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ABSTRACT: By exploiting cascaded second-order nonlinearities of a PPLN waveguide incorporated in a fibre based loop interferometer, we have experimentally demonstrated an optically controlled time and wavelength switch with a switching efficiency as high as 90.3%.
Optical Fibre Technology/Australian Optical Society, 2006. ACOFT/AOS 2006. Australian Conference on; 08/2006
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ABSTRACT: We have experimentally demonstrated an all-optical data extraction of a 10 Gb/s user-selected WDM channel using cascaded second-order nonlinearities of a PPLN waveguide incorporated in a fiber based loop interferometer.
Optical Internet and Next Generation Network, 2006. COIN-NGNCON 2006. The Joint International Conference on; 08/2006
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ABSTRACT: We first report on error-free tunable all-optical wavelength conversion of 160 Gbit/s return-to-zero signals based on cascaded sum-frequency and difference-frequency generation in a periodically poled LiNbO<sub>3</sub> waveguide. The BER of less than 10<sup>-9 </sup>is achieved in 23 nm tuning range.
Optical Fiber Communication Conference, 2006 and the 2006 National Fiber Optic Engineers Conference. OFC 2006; 04/2006
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ABSTRACT: We propose a unique design of a time-of-flight laser ranger that detects the distance and reflectivity of a target based on cross-gain modulation between counter-propagating pulses in a semiconductor optical amplifier, without using high-speed electronics.
Optical Fiber Communication Conference, 2006 and the 2006 National Fiber Optic Engineers Conference. OFC 2006; 04/2006
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N Wada, S Shinada,
H Furukawa,
M Fricke,
J Röse,
R Herber,
R Ries,
T Cinkler,
P Soproni,
G Sallai,
others
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電子情報通信学会技術研究報告. PN, フォトニックネットワーク. 110(95):49-54.