共查询到20条相似文献,搜索用时 15 毫秒
1.
Describes an optical transmission system operating at a data rate of 16 Gbit/s and a wavelength of 1.3 mu m. A transmission distance of 53 km was obtained with an etched-mesa DFB laser and a hybrid pin/HEMT receiver.<> 相似文献
2.
A single-mode optical time-domain reflectometer (OTDR) operating at a wavelength of 1.3 ?m with a dynamic range in excess of 26 dB one way is reported. The equipment incorporates a semiconductor laser source and a new low-noise optical receiver design utilising a PIN diode detector and a transimpedance amplifier. 相似文献
3.
Edge-emitting 1.3 ?m LEDs are used to launch -13·7 dBm of average optical power into single-mode fibres. This permits analogue video signal transmission over a distance of 42 km with a loss margin of 5 dB. No degradations of DG, DP or signal-to-noise ratio have been observed. 相似文献
4.
Dongsoo Bang Jongin Shim Joongkoo Kang Minsik Um Sangmin Park Sangmoon Lee Donghoon Jang Yungseon Eo 《Photonics Technology Letters, IEEE》2002,14(9):1240-1242
1.3-/spl mu/m uncooled InGaAsP-InP loss-coupled distributed feedback lasers operating over 10 Gb/s and at 85/spl deg/C were successfully fabricated. In order to achieve high-speed and high-temperature operation simultaneously, the following are thoroughly investigated: modulation-doped and strain-compensated multiple-quantum-well active layers, Fe-doped buried-heterostructure, coupling coefficient of loss-coupled grating, detuning lasing wavelength from the gain peak, and facet coatings. The authors also demonstrate 10 Gb/s transmission with negligible dispersion power penalty over 20 km of nondispersion-shifted fiber at 10 Gb/s for temperatures ranging from 25/spl deg/C to 85/spl deg/C. 相似文献
5.
Single-mode and high-power operation at temperatures up to 120°C has been achieved in 1.3-μm strained MQW gain-coupled DFB lasers. A stable lasing wavelength is maintained due to a large modal facet loss difference of the two Bragg modes, which is provided by the gain-coupling effect. A very low temperature dependence of the threshold current has been obtained by detuning the lasing wavelength to the long wavelength side of the material gain peak at room temperature, which effectively compensates the waveguide loss at higher temperatures. An infinite characteristic temperature To can be realized at certain ranges of temperature depending on the detuning value 相似文献
6.
Light emission from the /sup 1/G/sub 4/ to /sup 3/H/sub 5/ transition around 1.3 mu m of Pr/sup 3+/ has been studied in fluoride glass (ZBLAN) fibres. Pumping at 1064 nm yields extracted laser power of a few mW at 1.294 mu m. Gain curves centred at 1.295 mu m have been obtained, with gross gains of more than 15 dB at 1.319 mu m. Changes of the output ASE with pumping conditions are explained by excited state absorption or energy transfer from the /sup 1/G/sub 4/ upper level of the transition.<> 相似文献
7.
By using an ultra-low capacitance structure, the wavelength dependence, 1.3 or 1.55 mu m, of the intrinsic modulation bandwidth relating to the relaxation oscillation frequency and the nonlinear damping in GaInAsP DFB lasers is investigated.<> 相似文献
8.
Reports on the performance of GaInAsP/InP DFB lasers with Zn-doped active region. At both 1.3 and 1.55 mu m the authors achieved a large bandwidth owing to the increased differential gain. The carrier lifetime of the lasers decreased with doping level. The decreased carrier lifetime had the effect of reducing the pattern effect, and they could obtain a clear eye opening with 4 Gbit/s NRZ modulation.<> 相似文献
9.
10.
Laser emission and amplification have been studied in the 1.3 mu m spectral region on the /sup 4/F/sub 3/2/-/sup 4/I/sub 13/2/ transition in Nd/sup 3+/-doped fluorophosphate singlemode fibres. Pumping at 800 nm yields an extracted laser power of 10 mW at 1.323 mu m. A gain higher than 3 dB was obtained at the same wavelength in the amplifier experiment.<> 相似文献
11.
F. Grillot B. Thedrez O. Gauthier-Lafaye M.F. Martineau V. Voiriot J.L. Lafragette J.L. Gentner L. Silvestre 《Photonics Technology Letters, IEEE》2003,15(1):9-11
The onset of the coherence-collapse threshold is theoretically and experimentally studied for monomode 1.3-/spl mu/m antireflection/high reflection distributed-feedback lasers taking into account facet phase effects. The variation of the coherence collapse from chip to chip due to the facet phase is in the range of 7 dB and remains almost independent of the grating coefficient. Lasers that operate without coherence collapse under -15-dB optical feedback, while exhibiting an efficiency as high as 0.30 W/A, are demonstrated. Such lasers are adequate for 2.5 Gb/s isolator-free transmission without under the International Telecommunication Union recommended return loss. 相似文献
12.
Gnauck A.H. Jopson R.M. Burrus C.A. Wang S.-J. Dutta N.K. 《Photonics Technology Letters, IEEE》1989,1(10):337-339
A 16 Gb/s electrically time-division-multiplexed lightwave link is discussed. The 16 Gb/s electronic signal was generated by multiplexing together eight copies of the 2-Gb/s pseudorandom sequence (length 215-1) produced by a commercial BER test set. A 22-km transmission distance was achieved using a directly modulated, 1.3-μm wavelength DFB laser and a 50-Ω p-i-n receiver. Receiver sensitivity for a BER of 10-9 was -2.0 dBm. The addition of an optical preamplifier required a more sensitive receiver to avoid saturation-induced distortion in the preamplifier. This was accomplished by reducing the 2-Gb/s word length to 24 b, thereby lowering the intersymbol interference penalty and effectively increasing the receiver sensitivity. Under these conditions, the optical preamplifier receiver sensitivity was -19 dBm, and a 64.5-km transmission was demonstrated 相似文献
13.
Polarisation mode delay differences in three single-mode fibres were measured interferometrically at 1.3 ?m with a resolution below 25 fs. Polarisation mode dispersion increases strongly with core ellipticity. 相似文献
14.
Generation of <3 ps full width at half maximum (FWHM) 1.3 mu m pulses by compressing the chirped output of a gain-switched distributed feedback laser diode (DFB-LD) with a fibre dispersive delay line is reported. Diode laser requirements for minimum pulse width and maximum pulse energy, as well as suppression of 'wings' on the optical pulse, are discussed.<> 相似文献
15.
Linewidth enhancement factor of 1.3 mu m InGaAsP/InP strained-layer multiple-quantum-well DFB lasers
The linewidth enhancement factor alpha in a 1.3 mu m InGaAsP/InP strained-layer multiple-quantum-well (SL-MQW) distributed feedback (DFB) laser has been evaluated from the relation between the frequency and intensity modulation indexes, and the spontaneous emission spectra below threshold current. It is demonstrated that the measured alpha -parameter of a 1.3 mu m SL-MQW DFB laser is about two, and is much smaller than that in a conventional bulk DFB laser. From the resonance frequency dependence on the output power, it is concluded that this reduction of the alpha -parameter originates in the increased differential gain. The reduction of wavelength chirping, as a result the low alpha -parameter, was experimentally confirmed for the SL-MQW DFB laser.<> 相似文献
16.
Y.C. Lee W.K. Yuen C. Shu 《Photonics Technology Letters, IEEE》1996,8(9):1154-1156
A simple configuration to generate tunable single-mode pulses by self-injection seeding of a gain-switched semiconductor laser is demonstrated. The key part of the setup consists of a highly dispersive fiber and a fiber mirror. The configuration shows improved stability and promise to operate at both 1.3 and 1.55 /spl mu/m. The lasers at the respective wavelengths have been successively tuned over 13.43 and 12.81 nm with a side-mode suppression ratio >15 dB. Continuous access of wavelength with an enhanced tuning range is also achieved by combining both electrical and thermal control on the laser. 相似文献
17.
Machida Susumu Jun-Ichi Yamada Mukai Takaaki Horikoshi Yoshiji Tsuchiya Haruhiko Miya Tetsuo 《Electronics letters》1979,15(8):219-221
By using an InGaAsP semiconductor laser emitting at 1.5 ?m, where silica fibre loss is at a minimum, single-mode fibre transmission experiments were successfully carried out at 100 Mbit/s with about 30 km repeater spacing, 400 Mbit/s transmission characteristics using 20 km fibres are also reported. 相似文献
18.
Chih-Wei Hu Feng-Ming Lee Kun-Fu Huang Meng-Chyi Wu Chia-Lung Tsai Yin-Hsun Huang Lin C.-C. 《Photonics Technology Letters, IEEE》2006,18(14):1551-1553
In this letter, we proposed an alternate method by using the Fe-doped InGaAsP-InP hybrid grating layers to fabricate the 1.3-/spl mu/m current-blocking-grating complex-coupled distributed-feedback (CBG CC-DFB) laser diodes (LDs) grown by metal-organic chemical vapor deposition (MOCVD). By combining the Fe-doped InGaAsP-InP grating layers, the CBG CC-DFB LDs can provide high optical DFB coupling coefficient and high current confining ability. Moreover, the current aperture in the lateral direction can be easily controlled by the self-aligned MOCVD regrowth process. Therefore, the manufacture of CBG CC-DFB buried heterostructure LDs is easy as the ridge-waveguide LDs. The LDs exhibit a low threshold current of 5.3 mA, a high slope efficiency of 0.42 mW/mA, and a stable single mode with a high sidemode suppression ratio of /spl sim/42 dB at two times the threshold (10.5 mA). Even at high temperatures, these LDs still have an extremely low threshold current of 15.8 mA at 90/spl deg/ and a small variation in slope efficient of only -1 dB at the temperatures between 20/spl deg/ and 80/spl deg/. Furthermore, these LDs show a high-speed characteristic of more than 11.8 GHz at 20/spl deg/, which are suitable for 10-Gb/s Ethernet and OC-192 applications. 相似文献
19.
Wavelength tunability over 5 AA at narrow linewidths (less than 10 MHz) and high-output powers (over 15 mW/front facet) is demonstrated in long-cavity multielectrode distributed-feedback (DFB) lasers for coherent optical transmission systems.<> 相似文献
20.
A 3-dB bandwidth of 20 GHz has been demonstrated for a compressively strained multiquantum well InGaAsP-InP DPB laser operating at 1.3 μm. The laser displayed superior static performance including very low threshold current (~8 mA), high external quantum efficiency (0.44 mW/mA), high CW output power (>60 mW) and high temperature operation 相似文献