A comparative photoluminescence study on Mn-Free GaAs/AlAs and Mn-containing Ga_1-xMn_xAs/AlAs quantum wells (QWs) grown on various orientations by MBE

Structural and optical properties of diluted magnetic $$\hbox {Ga}_{{1-x}}\hbox {Mn}_{{x}}$$ Ga 1 - x

“…This might be attributed to residual concentration of Mn (residual impurity), which incorporates into the structure even after the Mn shutter is closed, inducing non-homogenous surface. Gunes et al [15] and Rodrigues et al [18] recently reported PL results of (100) GaAs-AlAs QW structure with and without Mn content. The temperature-dependent PL spectrum in Mn-free GaAs-AlAs QW sample had a shallow donor, which was assigned to interstitial Mn i .…”

“…Adding very low Mn content into the structure leads to a reduction of As defects and allows the substitutional incorporation of Mn into Ga sites, enabling the observation of optical emission from GaMnAs QW (see figures 1b-4b). Further details can be found in reference [15]. Figure 5 shows the XRD pattern of GaMnAs QW grown at 450…”

“…The Mn content is kept low in order to avoid high density of defects. In fact, it was reported that for this low Mn composition the As defects are reduced and the substitutional incorporation of Mn into Ga sites is enhanced, which enabled the observation of optical emission [15]. The crystal quality of our QWs was determined by X-ray diffraction (XRD) measurements.…”