Anomalous small angle X-ray scattering study of CdTe quantum dots in ZnTe

Anomalous small angle X-ray scattering (ASAXS) from the molecular beam epitaxially grown multilayers of quantum dots CdTe separated by ZnTe layers on the ZnTe/CdTe/GaAs(001) support has been observed. The first sample denoted 15 ML contained 200 layers of 2.5 ML CdTe/15 ML ZnTe and the second sample denoted 75 ML contained 200 layers of 2.5 ML CdTe/75 ML ZnTe. An enhancement of scattering by quantum dots was observed for photon energy near the Zn K absorption edge. We found that the ASAXS from the 15 ML sample was by one order of magnitude higher than that from the 5 ML sample, which means that the number of quantum dots in the 15 ML sample was one order of magnitude bigger than in the 75 ML sample. The scattering curves indicate a broad size distribution of quantum dots in both samples.