E.U. Rafailov

High-power picosecond and femtosecond pulse generation from a two-section mode-locked quantum-dot laser

We demonstrate mode locking in a two-section quantum-dot laser that produces output powers up to 45 mW at 1260 nm. The pulse duration could be varied from 2 ps to as short as 400 fs at the 21 GHz pulse repetition rate.

Amplification of femtosecond pulses over by 18 dB in a quantum-dot semiconductor optical amplifier

We demonstrate amplification (> 18 dB) of 200-fs pulses in a quantum-dot (QD) semiconductor amplifier. Our measurements have shown that such QD devices can provide amplification of femtosecond pulses over a spectral range that exceeds 100 nm.

Quantum-dot-based saturable absorber with p-n junction for mode-locking of solid-state lasers

We demonstrate stable mode-locking in a Yb : KYW laser by using a quantum-dot (QD) saturable absorber structure that incorporates a p-n junction. A reduction in the output pulse duration was measured when a reverse bias was applied to the QD saturable absorber mirror.

Efficient frequency doubling of a pulsed laser diode by use of a periodically poled KTP waveguide crystal with Bragg gratings

Blue light with an average power of as much as 7.5 mW in picosecond pulses has been generated at 486, 488, and 491 nm from a frequency-doubled, nonresonant injection seeded, gain-switched InGaAs/GaAs diode laser by use of a periodically poled KTP waveguide crystal that incorporates a Bragg grating section.

Broadband tuning and dual-spectral/temporal outputs from a nonresonantly injection-seeded diode laser

We demonstrate spectral narrowing and continuous broadband tuning of the picosecond pulse outputs from a nonresonantly injection-seeded, gain-switched diode laser that can be operated in dual spectral/temporal regimes. A single spectral output was continuously tunable over a range of 85 nm and in a dual-wavelength operation the outputs had spectral separations were adjustable from 3.5 to 53 nm.

Ground and excited-state modelocking in a two-section quantum-dot laser

We demonstrate, for the first time, stable mode-locking and ultrashort-pulse generation via ground or excited states from a two-section quantum-dot laser. The change of generation between these states in the mode-locking regime is fully controllable.

Efficient femtosecond green-light source with a diode-pumped mode-locked Yb3+:KY(WO4)2 laser

Efficient generation of femtosecond pulses at 524 nm is demonstrated by the extracavity frequency doubling of the output of a diode-pumped femtosecond Yb3+:KY(WO4)2 laser using a periodically poled LiTaO3 crystal. An average second-harmonic power of 120 mW is produced at an internal conversion efficiency of 40%. The temporal characteristics of the frequency-doubled pulses as a function of focusing conditions in a thick nonlinear crystal are investigated experimentally, and pulses as short as 225 fs are generated at a pulse repetition frequency of 86 MHz.

High-power laser structures incorporating novel curved-gratings

We present a theoretical investigation a novel type of distributed feedback laser with a “curved-groove” diffraction grating (c-DFB), which is predicted to give an enhanced spectral and spatial output characteristics.

Efficient direct frequency conversion of a non-resonant injection-seeded laser diode using a periodically-poled KTP waveguide crystal

Summary form only given. There is considerable interest in compact lasers that operate in the blue spectral region. A blue laser source combining a diode laser with a waveguided nonlinear crystal represents such a compact source which is also stable, self-contained and has a low overall cost. By using a picosecond-pulse diode laser with a periodically-poled KTP waveguide crystal a coherent blue source at an average power of 3.9 mW has been demonstrated. To achieve efficient second harmonic generation (SHG) from the diode laser we designed a two-section waveguide crystal with a periodic grating structure and a Bragg grating, where this grating was fabricated to facilitate non-resonant injection seeding of the diode laser.

Highly efficient femtosecond Yb:KYW laser pumped by a single narrow-stripe laser diode

Yb-doped crystals have attracted strong interest during past few years especially in the development of efficient, simple and robust diode-pumped femtosecond lasers in the 1/spl mu/m spectral range. This article deals with the development of a low-threshold and highly efficient femtosecond Yb:KYW laser that incorporates a low-loss semiconductor saturable absorber mirror (SESAM) for self-starting mode-locking and a narrow-stripe InGaAs laser diode as a pump source.