Edik U. Rafailov

Tunable operation of a gain-switched diode laser by nonresonant self-injection seeding

We report tunable operation of a gain-switched diode laser by nonresonant self-injection seeding from an uncoated glass slide used as an external cavity reflector. A spectral linewidth reduction from 11 to 0.05 nm has been achieved for picosecond pulses with little effect on other laser characteristics. Good agreement with numerical simulations based on a compound-cavity laser model is also reported.

Stable modelocked operation from a quantum-dot laser in a broad temperature range

We demonstrate stable modelocking operation in a two-section quantum-dot laser at temperatures ranging from 20/spl deg/C to 80/spl deg/C. The level of reverse bias, from which stable mode locking exists, was found to be lower for higher temperature.

Efficient THz Radiation from Nanocrystalline Silicon-Based Multilayer Photomixer

In this paper we propose and model a novel multiple-layer photomixer based on amorphous/nano-crystalline-Si. The output power from such a photomixer is at least 10 times higher than conventional LTG-GaAs photomixers at 1 THz.

Investigation of transition dynamics in a quantum-dot laser optically pumped by femtosecond pulses

We investigated the behaviour of a quantum-dot edge-emitting laser, optically pumped by femtosecond pulses. We demonstrated that pulses generated by the laser from ground-state transitions have longer durations than those generated by the excited-states.

Efficient frequency doubling of femtosecond pulses in a periodically-poled LiTaO/sub 3/ crystal at room temperature

Here we report efficient generation of femtosecond pulses at 525 nm by the extracavity frequency doubling of the output of a diode-pumped mode-locked Yb:KYW laser using a periodically-poled LiTaO/sub 3/ crystal (PPLT).

Design parameters of periodically-switched nonlinear structures for efficient nonlinear process.

In this work we propose the use of averaged coefficients as design parameters for quasi-phase matched structures based on a periodically-switched nonlinearity (PSN) technique. We analyze theoretically a potential efficiency-enhancing geometry that is based on AlGaAs and GaAs/Si structures and compared with PPLN.

Frequency-doubling of a compact femtosecond Cr:LiSAF laser using a periodically-poled KTP waveguide crystal

We have investigated a very simple, extracavity single-pass scheme for frequency doubling in a periodically-poled KTP crystal waveguide. This sample was 11 mm in length and was poled for the frequency doubling of /spl sim/850 nm light. The channel guide had cross-sectional dimensions of /spl sim/4/spl times/4 /spl mu/m and was fabricated by ion exchange technique. The poled section was approximately 8 mm in length followed by a 3 mm Bragg-reflector section. Although the inclusion of this Bragg section, which reflected 26% of the fundamental, was intended for another application, it did not appear to affect the performance of the source laser. The observed saturation of the SHG efficiency in the ppKTP waveguide is attributed to pump depletion.

Tunable and multiple-wavelengths/temporal output from gain-switched diode laser and a four Bragg-grating fibre

In this paper we have demonstrated a single gain-switched InGaAs/GaAs diode lasers, and a four Bragg-grating fibres spectral narrowing, selective wavelength tuning and multiple picosecond pulses at four separate, discrete wavelengths. And it was found that the selection of the lasing wavelength was dependant upon the externally applied RF frequency of the gain-switched diode laser.