Electronic transport studies of Ag-doped Bi₂Se₃ topological insulator

The structural, magnetotransport, and angle-resolved photoemission spectroscopy (ARPES) of Ag-doped Bi₂Se₃ single crystals are presented. Temperature dependent resistivity exhibits metallic behavior with a slope change above 200 K for Ag-doped Bi₂Se₃. The magnetoresistance shows positive quadratic dependence at low fields satisfying Kohler's rule. Hall resistivity measurement shows that electrons are dominant charge carriers. Furthermore, these results agree well with the ARPES spectra observed at T = 20 K, where the Fermi level lies inside the bulk conduction band. The Dirac point of the topological surface states is shifted toward higher binding energy (∼0.12 eV) for Ag-doped samples as compared to pristine Bi₂Se₃.