Synthesis of (Bi_2Te_3)_x(TiTe_2)_x and (Bi_2Te_3)_x(TiTe_2)_3 Superlattices

摘要

The synthesis of (Bi_2Te_3)_x(TiTe_2)_x and (Bi_2Te_3)_x(TiTe_2)_3 Superlattices using modulated elemental reactants was successfully accomplished. This required the calibration of the deposition parameters to achieve both the desired atomic compositions of the constituent layers and the deposition of the absolute amounts of each of the components to yield the title compounds. Proper annealing conditions were determined from an investigation of the x-ray diffraction patterns of a superlattice sample as a function of annealing temperature. The change in lattice parameters as a function of x showed the expected linear behavior with slopes consistent with values expected from the published lattice parameters of the binary components. Rietveld refinement showed that the characteristic structure of the binary components is maintained in the Superlattices studied.