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1.
This paper reports on InGaAsP-InGaAsP tensile strained MQW electroabsorption (EA) modulators with a high modulation efficiency of 35 GHz/V that generate optical short pulses. We studied and optimized the multiple-quantum-well (MQW) structural parameters, barrier height, and well number, thickness, and strain in the absorption layer to ensure high attenuation efficiency and generate low duty cycle pulses. Low TE/TM polarization sensitivity was obtained by controlling strain. Stable, nearly transform-limited optical pulse trains with a narrow pulsewidth of 3.6 ps are generated by applying a 20-GHz sinusoidal modulation voltage (6 Vpp) to the EA modulator. This achieves a very small pulse duty cycle of 7.2% 相似文献
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A detailed analysis of the pulses generated with a multiple quantum well (MQW) electroabsorption (EA) modulator used as a soliton source is performed. The pulse temporal and spectral shape are simulated and a good agreement is obtained with the experimental results. An irregular holed spectrum shape is observed under certain operating conditions and its existence is attributed to parasitic phase modulation. This type of spectrum could be observed even for pulses having a time bandwidth τΔν product below 0.4 which makes them usually considered as nearly transform limited. However it is not the case. The influence of the pulse spectral shape on transmission performances is investigated by means of a realistic simulation of soliton pulse propagation at 10 Gb/s. It is shown that for 9000 km propagation distance and for pulses presenting this irregular spectral shape a signal degradation occurs as the timing jitter is above 10 ps and the quality factor Q is below 2, which results in an increase of the transmission bit error rate. In order to avoid the generation of this kind of pulses when operating a MQW modulator as a soliton source, a mapping is realized giving the adequate voltages to apply to the diode for acceptable soliton generation 相似文献
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Sahara R. Morito K. Sato K. Kotaki Y. Soda H. Okazaki N. 《Photonics Technology Letters, IEEE》1995,7(9):1004-1006
InGaAsP MQW electroabsorption modulators with and without compensated strain were fabricated and tested. Compensated strain was employed to reduce the valence band discontinuity between the well and barrier, which decreased the heavy-hole carrier escape time. A short optical pulse coupled into the modulator was used to measure the enhancement in carrier escape time from strained compensated InGaAsP quantum wells, for the first time. As a result, the strained MQW sample demonstrated an improved frequency response when operated at high optical input powers and low fields 相似文献
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H. Takeuchi K. Tsuzuki K. Sato M. Yamamoto Y. Itaya A. Sano M. Yoneyama T. Otsuji 《Photonics Technology Letters, IEEE》1997,9(5):572-574
NRZ operation at 40 Gb/s has been successfully performed using a very compact module of a multiple-quantum-well (MQW) electroabsorption modulator integrated with a distributed-feedback (DFB) laser. While the DFB laser is injected with a constant current, the integrated MQW electroabsorption modulator is driven with a 10-Gb/s electrical NRZ signal. A clearly opened eye diagram has been observed in the modulated light from the modulator. And a receiver sensitivity of -27.2 dBm at 10/sup -9/ has been experimentally confirmed in the bit-error-rate (BER) performance. 相似文献
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Wakita K. Kawamura Y. Yoshikuni Y. Asahi H. Uehara S. 《Quantum Electronics, IEEE Journal of》1986,22(9):1831-1836
The first measurements to be made of large anistropic electroabsorption and modulation of long-wavelength light propagating along the plane of InGaAs/InAlAs multiple quantum well (MQW) structures grown by molecular beam epitaxy (MBE) are reported. Photocurrent response of waveguide p-i-n diodes is studied for incident light polarization parallel and perpendicular to the MQW layers. Photocurrent increase with reverse bias throughout the entire photoresponse spectrum is observed for both polarizations. The MQW p-in optical modulator shows a capacitance-limited pulse response of 250 ps and the modulation depth is 14 percent. 相似文献
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Wood T.H. Burrus C.A. Tucker R.S. Weiner J.S. Miller D.A.B. Chemla D.S. Damen T.C. Gossard A.C. Wiegmann W. 《Electronics letters》1985,21(16):693-694
By incorporating two quantum wells into a capillary waveguide, we have made the first MQW optical modulator with an on/off ratio of at least 10:1. Furthermore, this device was used to generate an optical pulse less than 100 ps long, the fastest to date with an MQW device. 相似文献
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80 Gbit/s wavelength conversion using MQW electroabsorption modulator in delayed-interferometric configuration 总被引:1,自引:0,他引:1
Absorption recovery time and cross-phase modulation characteristics of an MQW electroabsorption modulator (EAM) were experimentally analysed. 80 Gbit/s error-free operation of a wavelength converter using the MQW EAM in a delayed-interferometer configuration was demonstrated for the first time. 相似文献
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Bigan E. Ougazzaden A. Huet F. Carre M. Carenco A. Mircea A. 《Electronics letters》1991,27(18):1607-1609
Efficient electroabsorption in an InGaAsP/InGaAsP MQW optical waveguide modulator structure is reported. A 17 dB extinction ratio is obtained by applying a 3.5 V drive voltage to a 78 mu m long waveguide operating at 1.54 mu m under TE-polarisation mode. The on-state attenuation is only 2 dB.<> 相似文献
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F. Devaux N. Souli A. Ougazzaden F. Huet M. Carre 《Photonics Technology Letters, IEEE》1996,8(2):218-220
We report on a tandem of electroabsorption modulators integrated with an amplifier by the identical active layer (IAL) approach. A 14 dB fiber-to-fiber is obtained by the use of constant As-P ratio MQW active layer and operation at 10 Gb/s is demonstrated. A record modulator saturation power of 35 mW is also reported. 相似文献
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Three MQW electroabsorption modulator structures made of 7, 13 and 20 wells are reported. The bandwidth is shown to increase linearly with intrinsic region thickness up to 40 GHz, with negligible penalty on the drive voltage which remains at less than 2 V. It is suggested that 100 GHz bandwidth should be reached with low drive voltage 相似文献
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The high-speed (20 Gbit/s) and highly efficient (2 V peak to peak for a 22 dB on/off ratio) operation of an MQW integrated electroabsorption modulator/DFB laser module is demonstrated. Output power from the module is over +3 dBm in the pigtailed singlemode fibre. To the authors' knowledge, this is the first report of 20 Gbit/s operation with a monolithically integrated light source 相似文献
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Souli N. Devaux F. Ramdane A. Krauz P. Ougazzaden A. Huet F. Carre M. 《Electronics letters》1994,30(20):1706-1707
Soliton generation and coding are obtained using a novel, and simple tandem integrated electroabsorption (EA) MQW modulator structure. Negligible electrical crosstalk (<40 dB) is obtained due to the integration between the modulators, of an optical amplifier based on the same active layer. This also allowed a very low fibre to fibre insertion loss of 9 dB. The device was operated at 10 Gbit/s 相似文献
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Allovon M. Fouchet S. Harmand J.-C. Ougazzaden A. Rose B. Gloukhian A. Devaux F. 《Photonics Technology Letters, IEEE》1995,7(2):185-187
We present the technical approach and the preliminary device results on the first integration of a Wannier Stark (WS) electroabsorption (EA) modulator with a DFB laser on InP. The WS modulator active layer consists of a lattice matched InGaAs-InAlAs superlattice (SL) grown by solid source MBE. It is butt-coupled to a laser grown by AP-MOVPE whose active layer includes a strained InGaAsP-InGaAsP MQW stack. Device results cover static performances of integrated lasers and modulators, and measurements of high frequency characteristics (small signal bandwidth and 10 Gb/s eye diagram) 相似文献
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R.M. Lammert G.M. Smith S. Hughes M.L. Osowski A.M. Jones J.J. Coleman 《Photonics Technology Letters, IEEE》1996,8(6):797-799
The design and operation of multiple-quantum-well (MQW) wavelength-tunable distributed Bragg reflector (DBR) InGaAs QW lasers with nonabsorbing gratings and monolithically integrated external cavity electroabsorption modulators fabricated by selective-area MOCVD are presented. Uncoated devices exhibit CW threshold currents as low as 10.5 mA with slope efficiencies of 0.21 W/A from the laser facet. Wavelength tuning of 7 nm is obtained by injection current heating of the DBR section. These devices also exhibit extinction ratios of 18 dB from the modulator facet at a low modulator bias of 1 V, when measured with a broad-area detector. When coupled to a singlemode fiber, these devices exhibited high extinction ratios of 40 dB at a modulator bias of 1.25 V. 相似文献
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T. Ido M. Koizumi S. Tanaka M. Suzuki H. Inoue 《Photonics Technology Letters, IEEE》1996,8(6):788-790
We propose using MQW electroabsorption (EA) modulators as optical gates in wavelength-division-multiplexing (WDM) switching systems. A fabricated MQW-EA gate with integrated waveguides showed a high extinction ratio (>30 dB), a low polarization-dependent loss (0.3 dB), and a low wavelength-dependent loss (1.1 dB) within the gain band (1545-1560 nm) of erbium doped fiber amplifiers (EDFAs). Ultra-high-speed (<40 ps) switching of a WDM signal was demonstrated. 相似文献
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A wavelength-tunable 3.5 ps pulse generator, which employs an electroabsorption modulator (EAM), a fibre pulse compressor, and a self-phase-modulation (SPM)-based pulse reshaper, is developed. An EAM directly generates 21 ps pulses at a repetition rate of 10 GHz, which are compressed to 6 ps by a fibre pulse compressor. An SPM-based pulse reshaper then eliminates the large pedestal of the compressed pulses. Thus, 3.5 ps pulses with extinction ratio larger than 27 dB and timing jitter as small as 150 fs are obtained. 相似文献
19.
A novel waveguide electroabsorption modulator structure is proposed. In this structure, the resonator properties of a quarter-wave phase-shifted grating are combined with the electroabsorption properties of a multiple-quantum-well (MQW) waveguide. The theory and design considerations for such a distributed feedback MQW modulator are discussed. The performance characteristics of this structure are studied theoretically and compared with conventional MQW waveguide modulators. It is found that increased modulation bandwidth and reasonable optical bandwidths can be obtained over a device without feedback, and design tradeoffs are identified and explored 相似文献
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Devaux F. Harmand J.C. Bouadma N. Carre M. Huet F. 《Photonics Technology Letters, IEEE》1995,7(7):748-750
We propose a new type of electroabsorption modulator based on a npipn diode structure. Its transmission curve versus applied bias should be symmetrical with respect to zero bias. A npipn InGaAs-InAlAs multiple-quantum-well (MQW) modulator has been fabricated to experimentally demonstrate two applications for optical fiber transmission systems: pulse generation with adjustable duty cycle for optical time division multiplexing and harmonic generation up to 40 GHz for millimeter radiowave transport on optical fiber 相似文献