Dual-wavelength mode-locked quantum-dot laser, via ground and excited state transitions: experimental and theoretical investigation.

University of Dundee, School of Engineering, Physics and Mathematics, Dundee DD1 4HN, UK.
Optics Express (Impact Factor: 3.53). 06/2010; 18(12):12832-8. DOI: 10.1364/OE.18.012832
Source: PubMed

ABSTRACT We report a dual-wavelength passive mode locking regime where picosecond pulses are generated from both ground (lambda = 1263 nm) and excited state transitions (lambda = 1180 nm), in a GaAs-based monolithic two-section quantum-dot laser. Moreover, these results are reproduced by numerical simulations which provide a better insight on the dual-wavelength mode-locked operation.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ground state gain dynamics of In(Ga)As-quantum dot excited state lasers are investigated via single-color ultrafast pump-probe spectroscopy below and above lasing threshold. Two-color pump-probe experiments are used to localize lasing and non-lasing quantum dots within the inhomogeneously broadened ground state. Single-color results yield similar gain recovery rates of the ground state for lasing and non-lasing quantum dots decreasing from 6 ps to 2 ps with increasing injection current. We find that ground state gain dynamics are influenced solely by the injection current and unaffected by laser operation of the excited state. This independence is promising for dual-state operation schemes in quantum dot based optoelectronic devices.
    Applied Physics Letters 06/2014; 104(26):261108-261108-4. DOI:10.1063/1.4885383 · 3.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents the current status of our research in mode-locked quantum-dot edge-emitting laser diodes, particularly highlighting the recent progress in spectral and temporal versatility of both monolithic and external-cavity laser configurations. Spectral versatility is demonstrated through broadband tunability and novel mode-locking regimes that involve distinct spectral bands, such as dual-wavelength mode-locking, and robust high-power wavelength bistability. Broad tunability of the pulse repetition rate is also demonstrated for an external-cavity mode-locked quantum-dot laser, revealing a nearly constant pulse peak power at different pulse repetition rates. High-energy and low-noise pulse generations are demonstrated for low-pulse repetition rates. These recent advances confirm the potential of quantum-dot lasers as versatile, compact, and low-cost sources of ultrashort pulses.
    IEEE Journal of Selected Topics in Quantum Electronics 09/2011; 17(5):1302-1310. DOI:10.1109/JSTQE.2011.2141119 · 3.47 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Wavelength bistability and tunability are demonstrated in a two-sectional quantum-dot mode-locked laser with a nonidentical capping layer structure. The continuous wave output power of 30 mW (25 mW) and mode-locked average power of 27 mW (20 mW) are achieved for 1245 nm (1295 nm) wavelengths, respectively, under the injection current of 300 mA. The largest switching range of more than 50 nm and wavelength tuning range with picosecond pulses and stable lasing wavelengths between 1245 and 1295 nm are demonstrated for gain current of 300 and 330 mA.
    IEEE Journal of Selected Topics in Quantum Electronics 01/2013; 19(4):1100907. DOI:10.1109/JSTQE.2013.2239610 · 3.47 Impact Factor


Available from
Jan 8, 2015