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1.
MM. J. Duflos D. Letouz G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1083-1084
This communication describes the synthesis of l-methyl-2,3-diformylpyrrole. This new compound is used to prepare a new heterocycle, l-methylcyclohepta[b]pyrrol-6-one and thus allows a new synthesis of l-methylpyrrolo[2,3-d]pyridazine. 相似文献
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We present the design and experimental characterization of a monolithic optical time-division multiplexer (MUX) for 160 Gbit/s operation based on periodically poled lithium niobate (PPLN) waveguides. Its key figures of merit agree well with theoretical predictions and meet or exceed those of a previously demonstrated PPLN-planar-light-wave-circuit hybrid MUX. The monolithic design has a simpler layout and higher efficiency while keeping the cross talk low. 相似文献
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We describe theoretically a method of obtaining pulse compression and simultaneously improving amplification in a degenerate optical parametric amplifier by use of quasi-phase-matched engineered crystals. The scheme combines the possibility of increasing the signal spectral bandwidth that is offered by a degenerate parametric amplifier with the ability of engineered aperiodically poled crystals to compensate for group-velocity mismatch. 相似文献
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We demonstrate continuously tunable compensation of linear chirp on a first-harmonic pump pulse to produce a near-transform-limited second-harmonic output pulse through the use of a chirped, fanned, periodically poled lithium niobate quasi-phase-matching grating. Compensation of positive and negative chirps is possible through reversal of device orientation. The device is simple and monolithic and can be applied to compensation of a higher-order phase with minor modification. 相似文献
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We report difference frequency generation-based wavelength converters with multiple phase-matching wavelengths that use engineered quasi-phase-matching structures in LiNbO(3) waveguides. Multiple-channel wavelength conversion is demonstrated within the 1.5-mum band and between the 1.3- and 1.5-mum bands. With simultaneous use of M pump wavelengths, these devices can also be used to perform wavelength broadcasting, in which each of N input signals is converted into M output wavelengths. 相似文献
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Vodopyanov KL Levi O Kuo PS Pinguet TJ Harris JS Fejer MM Gerard B Becouarn L Lallier E 《Optics letters》2004,29(16):1912-1914
We demonstrate an optical parametric oscillator (OPO) based on GaAs. The OPO utilizes an all-epitaxially-grown orientation-patterned GaAs crystal that is 0.5 mm thick, 5 mm wide, and 11 mm long, with a domain reversal period of 61.2 microm. Tuning either the near-IR pump wavelength between 1.8 and 2 microm or the temperature of the GaAs crystal allows the mid-IR output to be tuned between 2.28 and 9.14 microm, which is limited only by the spectral range of the OPO mirrors. The pump threshold of the singly resonant OPO is 16 microJ for the 6-ns pump pulses, and the photon conversion slope efficiency reaches 54%. We also show experimentally the possibility of pump-polarization-independent frequency conversion in GaAs. 相似文献
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We demonstrate ultrasensitive intensity autocorrelation measurements of subpicosecond optical pulses in the telecommunication band by using aperiodically poled lithium niobate (A-PPLN) waveguides. The tightly confined optical beam in the waveguides and the chirped poling period facilitate simultaneous high second-harmonic generation (SHG) efficiency and broad phase-matching (PM) bandwidth. The resulting measurement sensitivity is 3.2 x 10(-7) mW2, approximately 500 times better than the previous record for intensity autocorrelations. We also show that chirped A-PPLN waveguides retain nearly the same SHG efficiency as the unchirped guide as long as the PM bandwidth is not significantly broader than the input spectrum. 相似文献