Our HRTEM images in Figure 2(c) and 2(d) show the lattice images (corresponding to the rectangle areas in Figure 2(a) and 2(b) respectively) of the two particles, from which we can clearly see BTS matrix, GaAs inclusions, and typical phase boundaries (between the matrix and the dispersed GaAs phase), as shown by dashed lines in Figure 2(c)&(d)