排序方式: 共有8条查询结果,搜索用时 31 毫秒
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Gee S. Ozharar S. Quinlan F. Plant J.J. Juodawlkis P.W. Delfyett P.J. 《Photonics Technology Letters, IEEE》2007,19(7):498-500
Noise characteristics are studied for a self-stabilized laser utilizing the interplay between the intracavity dispersion and the optical frequency shift. The noise suppression bandwidth of this scheme is from 0 to ~100 KHz and showed the reduction of residual timing jitter (integrated from 0.9 Hz to 1 MHz) from 2.2fs to 660 attosecond which represents, to our knowledge, the lowest timing jitter reported for an actively mode-locked laser 相似文献
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P.W. Juodawlkis J.J. Plant R.K. Huang L.J. Missaggia J.P. Donnelly 《Photonics Technology Letters, IEEE》2005,17(2):279-281
We report the first demonstration of a high-power semiconductor optical amplifier (SOA) based on the slab-coupled optical waveguide concept. This concept allows the realization of SOAs having large fundamental optical modes, low loss, and small optical confinement factor. These attributes support large output saturation power, long length for efficient heat removal, and direct butt-coupling to single-mode fibers. The 1.5-/spl mu/m InGaAsP-InP quantum-well amplifier described here has a length of 1 cm, 1/e/sup 2/ intensity widths of 4 /spl mu/m (vertical) and 8 /spl mu/m (horizontal), a fiber-to-fiber gain of 13 dB, and a fiber-coupled output saturation power of 630 mW (+28 dBm). The measured butt-coupling efficiency between the amplifier and SMF-28 is 55%. Thus, the output saturation power of the amplifier itself is approximately 1.1 W (+31 dBm). 相似文献
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Williamson R.C. Juodawlkis P.W. Wasserman J.L. Betts G.E. Twichell J.C. 《Lightwave Technology, Journal of》2001,19(2):230-236
Time interleaving of samples digitized by a parallel array of analog-to-digital (A/D) converters provides a means of increasing the sampling rate beyond that possible with a single A/D converter. For time-interleaved photonic A/D converters, optical demultiplexers can be used to advantage. Both time-division and wavelength-division demultiplexers must yield low crosstalk between the parallel output channels in order to yield accurate A/D conversion. An analysis predicts the level and form of the resulting errors. The analytical results compare well with experiment 相似文献
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Optical down-sampling of wide-band microwave signals 总被引:1,自引:0,他引:1
Juodawlkis P.W. Hargreaves J.J. Younger R.D. Titi G.W. Twichell J.C. 《Lightwave Technology, Journal of》2003,21(12):3116-3124
Phase-encoded optical sampling allows radio-frequency and microwave signals to be directly down-converted and digitized with high linearity and greater than 60-dB (10-effective-bit) signal-to-noise ratio. Wide-band electrical signals can be processed using relatively low optical sampling rates provided that the instantaneous signal bandwidth is less than the Nyquist sampling bandwidth. We demonstrate the capabilities of this technique by using a 60-MS/s system to down-sample two different FM chirp signals: 1) a baseband (0-250 MHz) linear-chirp waveform and 2) a nonlinear-chirp waveform having a 10-GHz center frequency and a frequency excursion of 1 GHz. We characterize the frequency response of the technique and quantify the analog bandwidth limitation due to the optical pulse width. The 3-dB bandwidth imposed by a 30-ps sampling pulse is shown to be 10.4 GHz. We also investigate the impact of the pulse width on the linearity of the phase-encoded optical sampling technique when it is used to sample high-frequency signals. 相似文献
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High-linearity 208-MS/s photonic analog-to-digital converter using1-to-4 optical time-division demultiplexers 总被引:2,自引:0,他引:2
Twichell J.C. Wasserman J.L. Juodawlkis P.W. Betts G.E. Williamson R.C. 《Photonics Technology Letters, IEEE》2001,13(7):714-716
This letter describes a demonstration of a photonic analog-to-digital converter operating at 208 MS/s and utilizing phase-encoded optical sampling to achieve an 87-dB two-tone third-order intermodulation-free dynamic range. A pair of LiNbO3 1-to-4 optical time-division demultiplexers with >35-dB channel extinction distribute the 30-ps sampling pulses to an array of photonic integrate-and-reset circuits followed by 12-b 52-MS/s electronic quantizers. Interleaving spurs due to temporal crosstalk currently limit the overall spur-free dynamic range to 65 dB 相似文献
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Gopinath J.T. Chann B. Huang R.K. Harris C. Plant J.J. Missaggia L. Donnelly J.P. Juodawlkis P.W. Ripin D.J. 《Photonics Technology Letters, IEEE》2007,19(12):937-939
Passively mode-locked 980-nm slab-coupled optical waveguide lasers have been demonstrated with pulse energies as high as 62 pJ and average powers of 489 mW at 7.92 GHz from a 5-mm device with a 300-mum absorber. Mode-locking has been observed with devices ranging from 3 to 10 mm in length 相似文献
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J.J. Plant P.W. Juodawlkis R.K. Huang J.P. Donnelly L.J. Missaggia K.G. Ray 《Photonics Technology Letters, IEEE》2005,17(4):735-737
We report the demonstration of high-power semiconductor slab-coupled optical waveguide lasers (SCOWLs) operating at a wavelength of 1.5 /spl mu/m. The lasers operate with large (4/spl times/8 /spl mu/m diameter) fundamental mode and produce output power in excess of 800 mW. These structures have very low loss (/spl sim/0.5 cm/sup -1/) enabling centimeter-long devices for efficient heat removal. The large fundamental mode allows 55% butt-coupling efficiency to standard optical fiber (SMF-28). Comparisons are made between SCOWL structures having nominal 4- and 5-/spl mu/m-thick waveguides. 相似文献
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