Injection-Locking Properties of InAs/InP-Based Mode-Locked Quantum-Dash Lasers at 21 GHz

Optical Frequency Comb Generation Using Dual-Mode Injection-Locking of Quantum-Dash Mode-Locked Lasers: Properties and Applications

“…This is a likely indication of suppression of free-running instabilities in pulses generated by the injectionlocked mode-locked laser. Third, in the optical spectrum of the injection-locked laser, spectral narrowing occurred in the vicinity of injection with significant portions of the spectral power in modes shifted to longer wavelengths by a few nanometers [18]. In Fig.…”

“…From now on, we call the laser with longer absorber "D 1 " and the device with shorter absorber as "D 2 ". Both devices operated in saturable-absorber dominated modelocked (SAML) regimes [18], [19] when the absorbers were biased well below the transparency point (≈0.9 V). The bias operational parameters of the device for SAML operation were typically around 100-200 mA for gain current and approximate absorber voltage of -0.6 V to 0.3 V for D 1 and -1.1 V to 0.3 V for D 2 .…”

“…When injectionlocking occurred, the RF linewidth significantly narrowed forming a delta-like RF lineshape (beyond the resolution limit of our electrical spectrum analyzer, 1 kHz), similar to hybrid mode-locking, with reduced noise level. This resulted in significant reduction of timing jitter by more than one order of magnitude (≈235 fs) [18], [23]. The RF locking-range is defined here as the spectral region where strong narrowing of the RF linewidth occurred accompanied by a lowering of the noise level by >30 dB (resolution bandwidth: 100 kHz).…”

Phase Synchronization of a Two-Channel Phase-Sensitive Amplifier based on Optical Injection-Locking of InP Quantum-Dash Mode-Locked Lasers

“…This is beneficial for this scheme, as only the injected modes were used as pump sources. Despite the fact that the spacing of extracted carriers were four times the repetition rate of injectionlocked laser, the same locking mechanism as dual-mode injection at first harmonic occurred [6]. The RF spectrum of the laser when free running (without injection) and under injection-locking is depicted in Fig.…”

“…This makes the overall setup complicated and bulky; therefore, a solution that would enable multiple pump generation by synchronizing a single laser comb-source is expected to be preferable. The possibility of coherent frequency comb generation using dual-mode (two coherent lines) injection locking of InP quantum-dash mode-locked lasers (QDMLLs) has recently been demonstrated [6]. This capability enabled phase synchronization of many comb lines to only two coherent CW lines.…”