1.55-μm mode-locked quantum-dot lasers with 300 MHz frequency tuning range

Abstract

Passive mode-locking of two-section quantum-dot mode-locked lasers grown by metalorganic vapor phase epitaxy on InP is reported. 1250-μm long lasers exhibit a wide tuning range of 300 MHz around the fundamental mode-locking frequency of 33.48 GHz. The frequency tuning is achieved by varying the reverse bias of the saturable absorber from 0 to −2.2 V and the gain section current from 90 to 280 mA. 3 dB optical spectra width of 6–7 nm leads to ex-facet optical pulses with full-width half-maximum down to 3.7 ps. Single-section quantum-dot mode-locked lasers show 0.8 ps broad optical pulses after external fiber-based compression. Injection current tuning from 70 to 300 mA leads to 30 MHz frequency tuning.

Time-Domain Traveling-Wave Analysis of the Multimode Dynamics of Quantum Dot Fabry–Perot Lasers

“…Recently, several experimental works on Quantum Dash (QDash) [13], [14] and Quantum Dot (QD) [15]- [18] lasers have shown the possibility of generating wide optical comb spectra with a single section FP cavity and, frequently, the emission of a pulse train directly at the laser output [15] or after propagation in a proper length of dispersive optical fiber [13], [17]. This phase locking regime obtained in a single section FP laser will be indicated hereafter as self-mode locking (SML) regime, to distinguish it from the passive-mode locking (PML) regime where a saturable absorber section is required.…”

Semiconductor nanostructures for flying q-bits and green photonics

“…Optical feedback is the method of choice to reduce jitter. Values of 121 fs for the integrated jitter were reported as well as tuning ranges of 300 MHZ around the fundamental mode locking frequency both for QD lasers emitting at 1.31 μm [17,18] and 1.55 μm [45].…”

“…Saturable absorbers based on QDs emitting at 1.3 μm were shown to exhibit fast recovery on the order of 700 fs under large reverse bias, enabling the generation of low chirp or chirp-compensated, Fourier-limited sub-picosecond pulses at frequencies of or beyond 80 GHZ, taking advantage of the large spectral width of the QD emission [42][43][44][45]. The timing jitter of MLLs is a result of random fluctuations of the photon density caused by amplified spontaneous emission (ASE).…”

“…Passively ML lasers (PMLLs) have the lowest cost, as they only incorporate an additional element in the cavity, a saturable absorber, which, as well as the gain section, is simply direct current (DC) biased. The absorber ensures self-start of ML, without an external radio-frequency (RF) reference source [42][43][44][45].…”

Design, fabrication, and investigation of 2 ?m GaSb-based diode lasers

“…For a monolithic mode-locked laser, frequency tuning can be achieved via the bias condition. For example, a tuning range of 300 MHz around the fundamental frequency of 33.48 GHz was reported in a 1.55 m mode-locked QD laser[37]. As we mentioned before, frequency tuning is also possible in hybrid mode locking by varying the external RF signal.…”