Mode oscillation and harmonic distortions associated with sinusoidal modulation of semiconductor lasers

This paper investigates mode dynamics, operation characteristics and signal distortions associated with sinusoidal modulation of semiconductor lasers. The study is based on intensive integrations of the multimode rate equation model of semiconductor lasers over wide ranges of the modulation frequency and depth. The rate equations take into account both spectral symmetric and asymmetric suppressions of modal gain. The higher harmonic distortions as well as the half harmonic distortion associated with the period doubling effect are investigated. The study is applied to both cases of single-mode and multimode oscillations of the non-modulated laser. The obtained results showed that the modulated signal has six distinct waveforms depending on the modulation conditions; three types have continuous periodic waveforms and the others have periodic pulsing waveforms. The modulated laser is found to oscillate in a single mode under weak modulation where the modulated signal is continuous, whereas the pulsing signals are associated with multimode oscillation. The higher harmonic distortions of single-mode laser are lower than those of two-mode lasers, and become serious at modulation frequencies around the relaxation oscillation frequency. These distortions are highest when the laser output is pulsating and the pulses are superposed by relaxation oscillations. © EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2012

Echo and ringing of optical pulse in finite photonic crystal with superconductor and dispersive dielectric

We study the transient pulse propagation in one-dimensional photonic crystal. Two new effects are identified: double reflection and slow-light ringing of transmitted and reflected pulses. We analyze these effects in superconductor-dielectric photonic crystal around the polariton resonance region of the dielectric material. Distinct double-polariton dispersions and narrow peaks in the transmission and reflection spectra are found when the plasma gap and the polariton gap of the dielectric overlap. Potential applications of these effect are discussed. (C) 2010 Optical Society of Americ

On approximate KNO scalling at {Mathematical expression} collider

10.1007/BF01452563Zeitschrift für Physik C Particles and Fields263381-38

Dissolution of Mg-based Mg-Ni-Nd amorphous alloys in 3% NaCl solution

Materials Letters361-4214-217MLET

Controlling quantum resonances in photonic crystals and thin films with electromagnetically induced transparency

Quantum coherence or phaseonium medium with electromagnetic-induced transparency (EIT) may have been widely explored, but the incorporation of boundaries into finite structures like thin films and photonic crystals introduce additional resonant features. A narrow transmission peak exists in resonant medium due to multiple reflections and interference. The corresponding analytical formulas for absorptive and EIT media are derived. A double dip feature is found only for transverse magnetic polarized light, due to longitudinal electric field component in a Fabry-Perot thin film. We study these resonant features in a finite superlattice and discuss potential applications of the features. For phaseonium medium with laser-driven gain, transmission and reflection peaks beyond unity appear between the two EIT resonances. Realizations using solid-state materials such as doped crystals and quantum dots with potential applications are discussed

Direct observation of a concealed glass transition in a Mg-Ni-Nd metallic glass

10.1063/1.1544441Applied Physics Letters826862-864APPL

Optical nonlinearities and photo-excited carrier lifetime in CdS at 532 nm

10.1016/S0030-4018(01)01066-5Optics Communications1901-6351-356OPCO

Effect of heat treatment on the corrosion behaviour of amorphous Mg-18 at% Ni alloy

Journal of Alloys and Compounds2792252-258JALC

Nonlinear refraction of undoped and Fe-doped KTiOAsO4 crystals in the femtosecond regime

Applied Physics B: Lasers and Optics703385-388APBO

Third-order nonlinear optical response in PbS-coated CdS nanocomposites

Journal of Materials Research1661644-1650JMRE