共查询到20条相似文献,搜索用时 46 毫秒
1.
Laporta P. Longhi S. Marchesi M. Taccheo S. Svelto O. 《Photonics Technology Letters, IEEE》1995,7(2):155-157
Third-order harmonic mode locking of a diode-laser pumped bulk Er:Yb:glass laser by frequency modulation with a lithium niobate modulator is reported. Stable pulses at a repetition rate of 2.5 and 5 GHz with a pulse duration down to 9.6 ps are obtained. The average output power is 3 mW, the pulse peak power is 120 mW at 2.5 GHz repetition rate, and the pulses are approximately 1.4 times transform limited. The pulse duration can be increased up to 30 ps by decreasing the mode-locker drive power 相似文献
2.
Cavelier M. Stelmakh N. Xie J.M. Chusseau L. Lourtioz J.-M. Kazmierski C. Bouadma N. 《Electronics letters》1992,28(3):224-226
A novel technique is used to produce picosecond wavelength-tunable optical pulses from gain-switched Fabry-Perot semiconductor lasers using fibre compression. Experiments are carried out with high power, large modulation-bandwidth lasers at 1.3 mu m. Pulses of 2.5 ps durations with repetition rates up to 12 GHz are obtained. Still shorter pulses ( approximately 1 ps) with higher repetition rates (18 GHz) are shown to be feasible.<> 相似文献
3.
van der Ziel J. Temkin H. Logan R. Dupuis R. 《Quantum Electronics, IEEE Journal of》1984,20(11):1236-1242
Gaussian shaped picosecond pulses as short as 62 ps have been obtained from an array of 10 phase-coupled multiquantum well GaAs lasers. Combined dc and 75 ps long current pulses from a comb generator were used. Single pulses were obtained with an average power of 50 mW at a 960 MHz repetition rate which corresponds to a peak power of 0.8 W. These pulse widths are in good agreement with a theory of pulse formation based on the carrier and photon density equations with the gain expanded in a power series in time to yield Gaussian pulses. 相似文献
4.
Vainshtein S. Rossin V.V. Kilpela A. Kostamovaara J. Myllyla R. Maatta K. 《Quantum Electronics, IEEE Journal of》1995,31(6):1015-1021
Optical pulses of ~100 ps duration, and ~102 W power were obtained from the industrial single heterostructure lasers with a standard pulse generation power of ~10 W in the internal Q-switching mode. Temporal and spectral analyses allow three components to be distinguished in the laser optical pulses: ordinary delayed pulses of large duration at energies considerably lower than the energy gap, short optical pulses caused by the gain-switching effect at higher energies, and short optical pulses at the end of the current pulse (Q-switching mode) at the highest energies. A model is proposed involving band tail states as a saturable absorber causing large delays 相似文献
5.
The author describes correlated and uncorrelated timing jitter of gain-switched pulses generated from sinusoidally modulated laser diodes measured from photocurrent power spectra. It is found that if dc bias is decreased to obtain shorter pulses, then the root-mean-square (rms) value of uncorrelated timing jitter drastically increases to more than 2 ps, while correlated jitter remains constant at the drive circuit level of ~0.2 ps. By optimizing the bias condition and compression fiber length, total timing jitter of gain-switched pulses can be reduced to as low as ~0.5 ps, as their pulse width is kept less than 10 ps 相似文献
6.
4 ps light pulses at repetition rates up to 10 MHz with an output power of some milliwatts are generated at 840 nm by directly modulating commercial GaAlAs V-groove lasers by specially designed avalanche generators. The pulses are measured using an ultrafast streak camera and present the fastest light pulses obtained until now by direct modulation of a semiconductor laser. The avalanche generators produce pulses of 125?200 ps FWHM with voltages up to 25 and 38 V, respectively. 相似文献
7.
4 ps light pulses at repetition rates up to 10 MHz with an output power of some milliwatts are generated at 840 nm by directly modulating commercial GaAlAs V-groove lasers by specially designed avalanche generators. The pulses are measured using an ultrafast streak camera and present the fastest light pulses obtained until now by direct modulation of a semiconductor laser. The avalanche generators produce pulses of 125?200 ps FWHM with voltages up to 25 and 38 V, respectively. 相似文献
8.
Hasnain G. Wiesenfeld J.M. Damen T.C. Shah J. Wynn J.D. Wang Y.H. Cho A.Y. 《Photonics Technology Letters, IEEE》1992,4(1):6-9
The authors report electrical gain-switching of a packaged vertical-cavity surface-emitting laser (VCSEL). Pulse durations as short as 24 ps at repetition rates up to 2 GHz were obtained from a four-quantum-well GaAs/AlGaAs VCSEL, which emits 0.8 mW continuous wave power in a single mode at room temperature and has a current threshold of 5 mA. Simultaneous measurement of the optical spectrum showed an almost transform limited linewidth indicating ultralow chirp. Optical pumping with subpicosecond pulses of the same packaged devices, held at a constant electrical bias, yielded 22 ps pulses, in good agreement with the electrical pumping. Simple calculations show that the pulse duration obtained by gain-switching is limited by the design constraints necessary to operate the VCSEL continuous wave at room temperature with low-threshold current, high-quantum efficiency, and reasonable output power 相似文献
9.
Single ultrashort optical pulses (2 ps with 17.6 GHz repetition rate) have been generated with hybrid mode-locked monolithic GaAs/AlGaAs lasers at lambda =856 nm. Instead of an external cavity, long active waveguides were used as resonators with a roundtrip frequency of 5.9 GHz. Increasing the pump current in the waveguide far above transparency led to 10 ps pulses with a high peak power of 110 mW.<> 相似文献
10.
T. Torounidis M. Westlund H. Sunnerud B.-E. Olsson P.A. Andrekson 《Photonics Technology Letters, IEEE》2005,17(2):312-314
Short return-to-zero pulses (/spl sim/2 ps) are generated at bit rates of 40, 80, and 160 Gb/s using a fiber-optical parametric amplifier. The performance of the parametric pulse source is evaluated both back-to-back and in a 110-km transmission link. A receiver sensitivity of -33 dBm back-to-back was achieved after demultiplexing from 160 to 10 Gb/s. The power penalty at 160 Gb/s due to 110-km transmission was less than 2 dB. Very short pulses (0.5 ps) were also achieved when using the parametric amplifier as a compressor. 相似文献
11.
以固态半导体器件为基础,基于超快电子学中的晶体管雪崩导通理论,利用脉冲耦合原理,在时域上将多路高压皮秒脉冲耦合输出,获得了超宽带高功率脉冲。通过四路脉冲耦合实验验证了该设计思路的可行性,提高了输出脉冲功率。实验中,单路高压皮秒脉冲的幅度为1.33kV,宽度为770ps,峰值抖动≤1%,脉宽抖动≤1%,四路脉冲耦合后,输出脉冲幅度为2.66 kV,宽度为875 ps,峰值抖动≤1%,脉宽抖动≤1%。该方法可以推广至多路脉冲耦合,获得更高的功率。 相似文献
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13.
A new technique is presented and investigated systematically which generates optical signals at millimeter-wave repetition rates from a semiconductor laser, without the need for an intracavity saturable absorber. Optical pulses are generated from a long-cavity semiconductor laser with a repetition rate equal to its cavity resonant frequency by injecting short optical pulses at one of the cavity resonance subharmonics. A rate-equation model is proposed to explain the mechanism of this subharmonic optical injection method. Optical pulses with repetition rates of 35 and 56 GHz are generated using the proposed scheme from a semiconductor laser with a distributed Bragg reflector and a Fabry-Perot laser diode, respectively. The performance of the generated pulses is also evaluated in terms of detected RF power at the repetition frequencies, the subharmonic suppression ratio, phase noise, and timing jitter as a function of frequency detuning, injected optical power, laser bias current, and, finally, the subharmonic number. It is found that the generated optical pulses exhibit large subharmonic suppression ratio (>17 dB), large locking ranges >400 MHz, low levels of phase noise (~-93 dBc/Hz@10 kHz) and timing jitter (<0.41 ps over 100 Hz to 10 MHz), and large tolerance to variations in operating parameters 相似文献
14.
Complete optical switching of 2-30 ps signal pulses in the 0.83-1.0 μm wavelength range is demonstrated using 50 ps control pulses at 1.053 μm in an optical-fiber Kerr modulator/switch. This is achieved using an initial temporal offset between the pulses and group velocity dispersion to enable the fast pulse to walk-through the slow one. It is shown that a minimum switching power results when the initial offset is one-half of the relative group delay. As an important corollary, complete switching can occur with a control pulse shorter than the signal pulse 相似文献
15.
High power bandwidth-limited picosecond pulses with peak powers in excess of 200 mW have been generated using 1.5 mu m multicontact distributed feedback laser diodes for the first time. The pulses have widths typically less than 10 ps, time-bandwidth products of as little as 0.24, and can be generated on demand at generator limited repetition rates of up to 140 MHz.<> 相似文献
16.
17.
Kim A. Youmans R.J. Zeto R. Weiner M. Fishback J. Tsinetakes J. Lalevic B. 《Microwave Theory and Techniques》1991,39(12):2026-2030
The generation of extremely narrow, high peak power pulses using an optically activated impulse generator is described. Radiative measurements at 1 Hz PRF have been conducted at pulse bias levels up to 15 kV, using an optical pulse from a Nd:YAG laser to trigger the device. The measured pulse from a wideband antenna has a pulsewidth of 1.5 ns with a risetime of 900 ps. The frequency spectrum of this radiated waveform ranged from 50 MHz to 1 GHz 相似文献
18.
The nonlinear optical loop mirror is used to suppress optical noise and residual coherent background between repetitive short optical pulses. An input pulse power fraction of only 0.6% is improved to 80% at the output of the device. The device is passive and, in principle, independent of wavelength, pulse width, pulse repetition rate, and input signal polarization. This technique can be used to generate high peak power pulses using a cascade of optical amplifiers. Here we report the generation of 140 ps square pulses with 2 kW peak power (0.3 μJ) at a repetition rate of 10 kHz 相似文献
19.
The feasibility for generating high-peak-power ultrashort optical pulses was demonstrated from a highly RF-modulated InGaAsP DC-PBH laser diode at 1.3 ?m for the first time. Measured pulse width is found to be approximately 28 ps at 7 mW averaged output power, and peak output power reached about 1.2 W at 210 MHz repetition frequency. Higher peak output and shorter optical pulses could be expected with this type of semiconductor diode laser in the near-infra-red region. 相似文献
20.
Yu-Tai Li Shi J.-W. Cheng-Yu Huang Nan-Wei Chen Shu-Han Chen Chyi J.-I. Ci-Ling Pan 《Photonics Technology Letters, IEEE》2008,20(16):1342-1344
A novel photonic transmitter for wireless terahertz (THz) impulse-radio (IR) communication is realized by monolithic integration of a GaAs-AlGaAs-based uni-traveling-carrier (UTC) photodiode with a substrate-removed broadband antenna. The device can radiate strong sub-THz pulses (20-mW peak-power) with a narrow pulsewidth (<2 ps) and wide bandwidth (100 ~ 250 GHz). The maximum average power emitted by our device, under the same THz time-domain spectroscopic setup, is around ten times higher than that of the low-temperature-grown GaAs-based photoconductive antenna, while with a much lower dc bias (9 versus 35 V). The bias-dependent peak output powers of our devices suggest their suitability for application as a data modulator/emitter for photonic THz IR communication. 相似文献