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The authors report a technology to make a distributed Bragg reflector laser with buried dielectric grating and band gap tuned reflector region. The Bragg reflector is constructed by high coupling coefficient gratings made of SiO2 and InP. The band gap of the reflector is blueshifted by self-aligned quantum well intermixing using the buried SiO2 grating itself. The photoluminescence peak wavelength can be shifted by ∼45 meV for the quantum well sample covered by SiO2 grating compared to thermal shift only at annealing temperature of 800 °C for 100 s. The enhanced interdiffusion is caused by the P vacancies generated at SiO2 and InP interfaces as proved by secondary ion mass spectroscopy. [ABSTRACT FROM AUTHOR] more...

Inductively coupled argon plasma-enhanced intermixing of InAs/InP quantum dots grown on InP substrate is investigated. Intermixing is promoted by the near-surface defects generated by plasma exposure in annealing at a temperature of 600 °C for 30 s. The annealing results in a maximum differential band-gap blueshift of 106 nm but a thermal shift of only 10 nm. Band-gap halftones are obtained by controlling the amount of near-surface defects via wet chemical etching on the plasma-exposed InP cap layer. No degradation of quantum-dot crystal quality due to the process has been observed as evidenced by photoluminescence intensity. [ABSTRACT FROM AUTHOR] more...

In this letter, we report the observation of the longitudinal mode grouping effect in the InGaAsP/InP multiquantum-well ridge waveguide laser. Two mode groups were observed and showed different behaviors with the changing of the injection current. The higher order lateral modes and the current spreading in the ridge waveguide structure is proposed to be responsible for this mode grouping phenomena. A one-step quantum-well intermixing process using the SiO2 electrical isolation layer itself was introduced and proved to be effective in improving the lateral electrical and optical confinement in a ridge waveguide laser structure as well as eliminating the mode grouping. [ABSTRACT FROM AUTHOR] more...

In this letter, we report on temperature-dependent anti-Stokes photoluminescence (ASPL) at an interface between partially ordered GaInP[sub 2] epilayer and GaAs substrate. It is found that the intensity of the ASPL depends strongly on temperature accompanying with a clear blueshift in energy. A localized-state luminescence model was employed to quantitatively interpret temperature dependence of the ASPL. Excellent agreement between the theory and experiment was obtained. Radiative recombination mechanism of the up-converted carriers was discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR] more...