ABSTRACT This paper reviews Al zGa 1-x-zIn xAs/Al uGa 1-v-uIn vAs/InP bulk and quantum well (QW) structures of varying composition and heterostructure geometry which were grown by molecular beam epitaxy (MBE) and characterized by photoluminescence (PL) as well as x-ray diffraction (XRD). To gain insight into the fundamental crystal quality, the principal limits of PL and XRD linewidths were investigated both experimentally and theoretically. The linewidths were studied as a function of composition, layer thickness, strain and number of periods. First, bulk layers were grown and studied. Second, QW samples were implemented including (i) unstrained layers, (ii) strained wells with unstrained barriers and (iii) complementarily strained wells and barriers, i.e. strain-balanced structures. Series of strain-balanced structures including compressively strained quaternary wells and tensile strained quaternary barriers were grown to study PL linewidths as a function of well widths, barrier widths and net strain. The structures with the largest QW widths show the smallest PL linewidths which can be explained by an interplay of interface roughness and alloy disorder fluctuations in the wells and barriers. Varying the amount of net strain in the samples, surprisingly a non-zero amount was found to provide smallest PL linewidths and highest PL intensities. The homogeneity in PL wavelength across 2”-wafers was found to be better for QW structures with quaternary wells than for those with ternary wells. Finally, AlGaInAs and GaInAsP heterostructures were compared with respect to interwell carrier transfer efficiencies, problems of technological implementation and intrinsic bandwidth limits for high-speed laser devices. AlGaInAs offers advantages from the physical point of view due to the more favourable band discontinuities and GaInAsP is beneficial from the technological point of view in terms of optoelectronic device fabrication. This review proceeds from basic research of carrier dynamics to applications in high speed laser devices. Throughout the review an expanded overview of the experimental and theoretical literature is given.
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