Compresion and dispersionless transmission of chirped 1.3 mu m DFB ps laser pulses in dispersion-shifted single-mode fibres

Optical pulse compression of high-speed gain-switched ps 1.3 mu m DFB semiconductor laser pulses in dispersion-shifted single-mode fibres is measured with a streak camera. The laser-red-shift chirp is compensated for by the negative chromatic fibre dispersion, resulting in pulse compression and 'dispersionless' transmission of 45 ps pulses over 12 km of fibre.<>     

Picosecond pulse generation of <5 ps from gain-switched DFBsemiconductor laser diode using linearly step-chirped fibre grating

4.4 ps pulses generated from a 1546 nm gain-switched DFB-SLD using a 6 mm long linearly step-chirped fibre grating represent a temporal compression factor of 4.3. The pulse source is stable. Compact and dispenses with the dispersion compensating fibre conventionally used for pulse compression     

Pulse width tunable subpicosecond pulse generation from an activelymodelocked monolithic MQW laser/MQW electroabsorption modulator

Actively modelocked pulses are generated from a 1.59 μm MQW laser integrated with an MQW electroabsorption modulator driven at the monolithic cavity frequency. The pulse width is controlled from 39 ps to 0.55 ps by changing the inverse bias voltage applied to the electroabsorption modulator and by linear pulse compression using a fibre     

Picosecond (<2.5 ps) wavelength-tunable ( approximately 20 nm) semiconductor laser pulses with repetition rates up to 12 GHz

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.<>     

40 GHz actively modelocked polarisation maintaining erbium fibrering laser

The first polarisation-maintaining actively modelocked erbium fibre ring laser (ML-EFRL) operating at a base rate of 40 GHz is presented. The laser generates highly stable and virtually transform-limited 1.2-1.9 ps pulses tunable over 40 nm with a timing jitter of <0.1 ps. These represent the shortest pulses and lowest timing jitter generated by a 40 GHz ML-EFRL     

All laser diode compression of 5 GHz picosecond pulses using cross-phase modulation in optical fibre

5 GHz pulses from a mode-locked semiconductor laser diode have been compressed from 10.5 to 4.6 ps by means of cross-phase modulation using a separate optically amplified mode-locked laser diode. By tuning the laser wavelengths symmetrically about the 1.55 mu m dispersion zero of an 11 km length of fibre, the effect of group velocity dispersion is minimised, ensuring that the fibre is used efficiently. The spectral broadening induced by the cross-phase modulation enables pulse compression in a dispersive fibre.<>     

Picosecond pulse generation with high extinction ratio employing electroabsorption modulator, fibre compressor, and self-phase-modulation-based pulse reshaper

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.     

Compact fully fibre integrated source of 100 fs pulses at 1.1 /spl mu/m based on compression in holey fibre

A simple, compact, fully fibre integrated source of /spl sim/100 fs pulses at a wavelength of 1.1 /spl mu/m is reported. 4 ps pulses at 1063 nm from a modelocked fibre laser were amplified to 23 mW in a ytterbium-doped fibre amplifier and subsequently propagated through 62 m of holey fibre with a zero dispersion wavelength at 1040 nm. Soliton formation, breakup and self frequency shift resulted in the formation of /spl sim/100 fs pulses at 1.1 /spl mu/m. Wavelength tunability from 1113 to 1220 nm is demonstrated.     

Transform-limited 5.6 ps optical pulse generation at 12 GHz repetition rate from gain-switched distributed feedback laser diode by employing pulse compression technique

12 GHz chirped optical pulses from a gain-switched 1.3 ?m distributed feedback laser diode are compressed to transform-limited 5.6 ps pulses by travelling through a dispersion shifted single-mode fibre with 46 ps/nm normal dispersion. A time-bandwidth product of 0.69 and a high on/off ratio of 20 dB are obtained for optimally compressed pulses.     

Dispersion compensation of 16 ps pulses over 100 km of step-indexfibre using cascaded chirped fibre gratings

The propagation of 16 ps data pulses over 100 km of step-index fibre using two cascaded chirped fibre gratings to achieve dispersion compensation is presented. At the output, the pulses are broadened slightly to 20 ps, indicating the potential for 50 Gbit/s operation     

Generation of 6.3 ps optical pulses at a 10 GHz repetition rateusing a packaged electroabsorption modulator and dispersion compensatingfibre

Sinusoidal modulation of an MQW InGaAsP/InGaAsP EA modulator at a 10 GHz repetition rate was used to generate optical pulses of width as low as 7 ps. Pulses were linearly compressed using 400 m of dispersion compensating fibre and approximately transform limited pulses of 6.3 ps width were measured     

Dispersion in a low-loss multimode fibre measured at three wavelengths

Short pulses from mode-locked lasers (neodynium/yttrium-iron-garnet and krypton) were used to measure mode and material dispersion in 20 m of a multimode fibre at 1060, 647 and 568 nm. Uniform illumination of the cone of acceptance at the input caused a 200 ps pulse to broaden to 400 ps.     

色散补偿法获得5GHz,6.8ps超短光脉冲

利用色散位移光纤压缩从１．５５μｍ增益调制ＤＦＢ激光器中出射的红移啁啾光脉冲。在最优光纤压缩长度下，光脉冲宽度由４２．６ｐｓ压缩至６．８ｐｓ，压缩比为６．３     

Pedestal-Free Pulse Source for High Data Rate Optical Time-Division Multiplexing Based on Fiber-Optical Parametric Processes

In this paper, an RF-driven pedestal-free cavity-less 40 GHz pulse source for generation of high-speed optical time-division multiplexing signal is presented. The pulse source is based on pulse compression by means of self-phase modulation in combination with subsequent filtering. Further compression and pedestal removal of the pulse was achieved in one-pump fiber-optic parametric amplifier seeded by a continuous-wave laser source. The obtained idler pulses were characterized by a full-width at half-maximum pulsewidth of 1.2 ps and an SNR of 36 dB. Generation of 320 Gb/s data stream with a Q-factor of 20 dB is successfully demonstrated using the proposed pulse source.     

Measurement of broadening of pulses in glass fibres

In the letter is reported the measurement of broadening of pulses in glass fibres using a GaAs injection laser diode as an emitter and a germanium photodiode as a detector. We found broadening of about 5 ps/m for a multimode fibre and 0.6 ps/m for a self-focusing glass fibre.     

540 fs light pulses at 1.5 μm with variable repetition rateusing a tuneable twin guide laser and soliton compression in adispersion decreasing fiber

A novel and simple method to generate ultra short light pulses with variable repetition rate is demonstrated. A wavelength modulated tuneable twin guide laser, emitting blue-chirped light, together with pulse compression in a standard single mode fiber is used to generate light pulses of 3 ps width. Amplification and further compression in a dispersion decreasing fiber leads to Fourier transform limited pulses of 1.87 ps width or to 540 fs pulses with a small pedestal     

Tunable modelocked bismuth-doped soliton fibre laser

A modelocked bismuth-doped soliton fibre laser is reported. A stable passively modelocked operation in an anomalous dispersion regime is achieved using a dilute nitride (GaInNAs)-based semiconductor saturable absorber mirror and a transmission grating pair for dispersion compensation. The laser generated 0.9 ps soliton pulses with a repetition rate of 7.5 MHz and wavelength tunable from 1153? 1170 nm. These are the shortest pulses obtained so far from Bidoped fibre lasers.     

Antisymmetric pulse generation using phase-shifted fibre Bragggrating

A 10 mm Bragg grating with a 0.18 nm (peak-to-peak) spectral response was designed to shape a train of 7 ps Gaussian pulses into antisymmetric Hermite-Gauss pulses. The pulses were characterised in the frequency and time domain. The presence of the phase shift was verified by propagation in standard fibre     

154 GHz polarisation-maintaining dispersion-managed activelymodelocked fibre ring laser

Optical pulses with a repetition rate of 154 GHz are generated directly from a polarisation-maintaining dispersion-managed fibre ring laser using fourth-order FM modelocking. External chirp compensation of the laser output yields transform-limited Gaussian pulses with 1.1 ps duration corresponding to a duty cycle of <0.2     

Matched photonic bandgap fibre and fibre Bragg grating dispersion for all-in-fibre stretch pulse amplification

Kilowatt peak power pulses with pulse durations of approximately 1.5 ps within 5% of transform limit using an all-fibre stretch pulse amplification system are demonstrated. Efficient high-quality stretch pulse amplification is achieved using a matched chirped fibre Bragg grating and low nonlinearity photonic-bandgap hollow-core fibre. The nearly ideal recompression highlights the robustness of ultra-short picosecond pulses to group delay ripple in chirped fibre gratings.