Extent and feature of lattice distortions around Ga impurity atoms in InSb single crystal

To clarify lattice distortions induced by adding Ga atoms in the InSb crystal, Ga Kα x-ray fluorescence holography (XFH) experiments were carried out on an In_0.995Ga_0.005Sb diluted mixed single crystal, and three-dimensional atomic images around the Ga atoms were reconstructed. Although the atomic images are located almost at ideal positions of the InSb crystal, some differences can be observed for only the first- and second-neighboring atoms. By combining them with x-ray absorption fine structure data, large spatial fluctuations of the first-neighboring atoms appear in the angular direction, which can be clarified from the present XFH results. From the XFH results, it is concluded that lattice distortions are limited within the second neighbors in this diluted mixed crystal, in contrast to five chemical bonds in a heavily doped mixed crystal of Zn_0.4Mn_0.6Te reported previously.