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Based on the generalized stochastic nonlinear Schrodinger equation, the effect of initial chirp on the broadband amplitude noise of supercontinuum generated in fiber normal dispersion regime is investigated numerically. The results show that, in the normal dispersion region, where the bandwidths of the obtained spectra are less sensitive to the initial chirp parameters of the input pulses, the nonlinear process is significantly affected by the initial chirp. An optimal input positive chirp will shorten the action time of intrapulse Raman scattering, and decrease the spectral broadband amplitude noise without bandwidth and flatness loss.

Boron-containing GaAsSb/GaAs quantum wells (QWs) with different antimony (Sb) mole fractions were grown by low-pressure metal–organic chemical vapor deposition for the first time. The effects of boron incorporation on the performance of GaAsSb/GaAs QWs are discussed. For samples with low compressive strain, injection of triethylboron can enhance the Sb content and increase the compressive strain, although boron incorporation can lead to a reduction in strain. This effect was less for strained GaAsSb/GaAs QWs, so the compressive strain of these QWs did not vary. Room-temperature photoluminescence emission at 1116 nm with a full-width at half-maximum (FWHM) value of 56 meV was obtained for strained BGaAsSb/GaAs QWs.

The epitaxy of GaAs/Si(001) has been carried out via inserting different buffer layers and different SLSs by MOCVD. High quality epilayers were obtained by AlAs buffer layer and GaAs0.85P0.15/GaAs SLS.

InAs/GaAs quantum dots (QDs) were grown by Metal-Organic Chemical Vapour Deposition (MOCVD) in the Stranski-Krastanow growth mode. The influence of growth parameters such as V/III ratio, growth temperature, QDs deposit thickness and the deposition rate of the overgrowth layer have been investigated. Through the room temperature photoluminescence (PL) spectra, we have obtained the quantum dots’ characters. The growth of QDs is very sensitive to the parameters, and the parameters influence the QDs quality nonlinearly. After an extensive study of these growth parameters, we achieve a balance of all the growth parameters with which InAs/GaAs QDs with 80meV of full width at half maximum (FWHM) at 1.12μm have been achieved.

In this research, 5-period highly-strained BInGaAs/GaAs multiple quantum wells (MQWs) have been successfully grown at 480-510ºC by LP-MOCVD. Room-temperature photoluminescence (RT-PL) measurements of BInGaAs/GaAs MQWs showed the peak wavelength as long as 1.17 μm with full-width at half maximum (FWHM) of only 29.5 meV. In addition, a slight blue-shift (∼18 meV) of PL peak energy of InxGa1-xAs/GaAs MQWs was observed after boron incorporation. It has been found boron incorporation ( 40%), the positive effect of boron incorporation prevailed, i.e., boron incorporation completely suppressed the thickness undulation and lead to the improvement of PL properties.

Highly-strained BInGaAs/GaAs quantum wells have been grown at low temperature by incorporating boron element into InGaAs/GaAs quantum wells. The effects of boron incorporation on the structural and optical properties of highly-strained InGaAs/GaAs QWs been investigated.