Josué Parra-Cetina

InP-Based Integrated Optical Pulse Shaper: Demonstration of Chirp Compensation

We demonstrate dispersion compensation for highly chirped optical pulses with an ultracompact optical pulse shaper. The device integrates a 20-channel arrayed waveguide grating with 20 phase modulators and 20 semiconductor optical amplifiers on a single chip of 6 × 6 mm2. The chip has been realized in an InP-based generic photonic foundry process, which enables a significant reduction in design effort using standardized building blocks.

Timing-jitter, optical, and mode-beating linewidths analysis on subpicosecond optical pulses generated by a quantum-dash passively mode-locked semiconductor laser

Timing-jitter measurements in optically generated subpicosecond pulses by a quantum-dash passively mode-locked semiconductor laser as a function of the bias current are reported. All the measurements are retrieved from a second-harmonic-generation frequency-resolved optical gating system. A decreasing trend in the pulse width and the associated timing jitter is found with the bias current. Additionally, the optical and mode-beating linewidths are analyzed in terms of both the mode wavelength and the bias current. From our results, we can conclude that once the optical modes are phase locked, the optical linewidth associated to every individual longitudinal mode of the device under test does not have a significant impact on the mode-beating signal on neither the pulse width nor its respective timing jitter.

Spectral amplitude and phase measurement of a 40 GHz free-running quantum-dash modelocked laser diode

We present a linear self-referenced measurement of the spectral amplitude and phase of a free-running quantum-dash modelocked laser diode. The technique is suitable for measuring optical signals with repetition rates up to 100 GHz. In contrast to many other linear techniques it requires no external electronic clock synchronized to the signal under test. Using this method we are able to compensate for the intracavity dispersion of the diode to demonstrate 500 fs pulses at a repetition rate of 39.8 GHz. We also use the technique to characterize the dependence of the diodes intracavity dispersion on the applied current.

Analysis of a narrowband terahertz signal generated by a unitravelling carrier photodiode coupled with a dual-mode semiconductor Fabry-Pérot laser

A narrowband terahertz signal generated by a unitravelling carrier photodiode (UTC-PD) interfaced with a dual-mode Fabry–Perot laser diode is demonstrated. A beat tone corresponding to the free spectral range is generated on the UTC-PD, and radiated by a transverse-electromagnetic-horn antenna. A terahertz signal at a frequency of 372 GHz, featuring a linewidth of 17 MHz is recorded by a subharmonic mixer coupled to an electrical spectrum analyzer. All components involved in this experiment operate at room temperature. The linewidth and the frequency of the emitted terahertz wave are analyzed, along with their dependency on dc-bias conditions applied to laser diode.

Wavelength Tunability of All-Optical Clock-Recovery Based on Quantum-Dash Mode-Locked Laser Diode Under Injection of a 40-Gb/s NRZ Data Stream

Wavelength tunability of an all-optical clock recovery operation based on a quantum-dash mode-locked Fabry-Pérot laser diode is experimentally investigated. Synchronization of the device to the injection of 40-Gb/s nonreturn-to-zero (NRZ) incoming data is assessed by analyzing both the carrier-to-noise ratio and the linewidth of the 40-GHz beat-tones measured at the mode-locked laser output. Under optical injection, beat-tone linewidths below 10 Hz are measured. Recovered clock pulses featuring a width of 1.6 ps are obtained irrespective of the wavelength detuning between the laser spectra and the optical carrier of the incoming data stream.

Experimental Investigation of the Optical Injection Locking Dynamics in Single-Section Quantum-Dash Fabry-Pérot Laser Diode for Packet-Based Clock Recovery Applications

An experimental study of the dynamics of a quantum-dash Fabry-Pérot passively mode-locked laser diode is presented. Firstly, the switching on and off characteristic times of the mode-locking mechanism with pulsed biasing current are assessed. Secondly, the locking and unlocking characteristic times to the injection of a 10-Gbps pseudo-random binary sequence of nonreturn-to-zero data are determined. The dynamics is analysed through the instantaneous frequency of the ~40 GHz beat-tone signal measured at the output of the laser under investigation, which after a frequency down-conversion stage, is recorded by a real-time oscilloscope. Experimental results indicate that a time of 5 ns characterizes the establishment of the passive mode-locking mechanism for a pulsed biasing current. A time of 20 ns has been measured for the synchronization of the quantum-dash laser diode to the injected 10 Gbps data sequence. In addition, the mode-locked laser diode de-synchronizes and switches to the free-running condition in also 20 ns after a holding time of ~ 100 ns.

320 Gb/s all-optical clock recovery and time de-multiplexing after transmission enabled by single quantum dash mode-locked laser

We report, to the best of our knowledge, the first demonstration of 320 Gb/s all-optical clock recovery and all-optical time de-multiplexing after 51 km transmission by exploiting single-quantum dash mode-locked laser diode (QD-MLLD). Based on injection locking of the QD-MLLD, the 40 GHz synchronized optical clock pulses were recovered from the 320 Gb/s with a pulse width of 1.9 ps and timing jitter of 135 fs, which allowed directly time de-multiplexing of 320-40 Gb/s without additional complex optoelectronic circuitry. The 320-40 Gb/s all-optical de-multiplexing was achieved with averaging a power penalty of 4.5 dB at BER of 1E-6.

Performance Assessment of 40 Gb/s Burst Optical Clock Recovery Based on Quantum Dash Laser

We report a 40 Gb/s burst mode optical clock recovery (BM-OCR) by injection locking a dynamically switched quantum dash mode-locked laser diode. We investigated in detail the performance of the BM-OCR operation after 52 km transmission. High quality BM-OCR after transmission is achieved with a locking time of ~25 ns, and 40 GHz recovered packet clock with 46 dB signal to noise floor suppression and 64 fs timing jitter (100 Hz to 1 MHz). The reported BM-OCR has a continuous tuning wavelength range from 1535 to 1560 nm, power dynamic range of no less than 6.7 dB. The frequency deviation tolerance of the BM-OCR is within -427 to +226 ppm at 39.813 Gb/s (OC-768 standard line rate), which is compliant with the specifications in the IEEE 40/100-Gb/s Ethernet standard. These results indicate the promising future applications of the proposed BM-OCR in high speed burst mode optical receiver.

Semiconductor optical amplifier-based heterodyning detection for resolving optical terahertz beat-tone signals from passively mode-locked semiconductor lasers

An all-optical heterodyne approach based on a room-temperature controlled semiconductor optical amplifier (SOA) for measuring the frequency and linewidth of the terahertz beat-tone signal from a passively mode-locked laser is proposed. Under the injection of two external cavity lasers, the SOA acts as a local oscillator at their detuning frequency and also as an optical frequency mixer whose inputs are the self-modulated spectrum of the device under test and the two laser beams. Frequency and linewidth of the intermediate frequency signal (and therefore, the beat-tone signal) are resolved by using a photodiode and an electrical spectrum analyzer.

Subharmonic All-Optical Clock Recovery of up to 320 Gb/s Signal Using a Quantum Dash Fabry–Pérot Mode-Locked Laser

In this study, we provide an experimental assessment of a quantum dash Fabry-Pérot mode-locked laser for all-optical clock recovery using data streams at 40, 80, 160, and 320 Gb/s. The data streams at 80, 160, and 320 Gb/s are phase coherent signals featuring no spectral component at 40 GHz. The 40 GHz recovered optical clock signal is characterized in terms of phase noise, timing jitter, dynamic power range, and wavelength dependence for the different data rates. Our experiments demonstrate a recovered optical clock signal from a 320 Gb/s data stream with a timing jitter of 94 fs and wavelength detuned by 23 nm. In addition, the performance of the optical time division multiplexing receiver at 80 and 160 Gb/s data signals employing the recovered clock as a demultiplexing control signal and as a clock for the bit-error-rate tester (BERT) is evaluated by bit error rate measurements on the demultiplexed data signals.