Investigation of structural, magnetic, and weak anti-localization properties of Bi₂Se₃ topological insulator (TI) doped with magnetic (Mn) and non-magnetic (In) elements

The present study explores the effect of magnetic (Mn) and non-magnetic (In) doping on structural, magnetic, and weak anti-localization properties of Bi₂Se₃ topological insulator (TI). The un-doped as well as Mn, In-doped Bi₂Se₃ are synthesized using a solid-state reaction method. The X-ray diffraction (XRD) along with Rietveld refinement reveals that, both Mn and In-dopants substitute the Bi-ion along with slightly interstitially incorporate in host Bi₂Se₃. It is also found that Bi-substitution is a little preferable for In-doping than Mn. The magnetic measurement represents diamagnetism of un-doped Bi₂Se₃ and ferromagnetism/ paramagnetism for Mn-doping, whereas In-doped Bi₂Se₃ shows a mixing of diamagnetism and Pauli paramagnetism. Electrical-transport establishes that In-doped Bi₂Se₃ preserves the host`s metallic nature; however, the arrest of metallic response is observed through the evidence of Kondo effect below 185K for high Mn-doping. More interestingly, the magneto-transport establishes that Mn-doping creates a prominent deviation in quantum weak anti-localization (WAL) feature of host Bi₂Se₃, whereas, In-doping shows a minor deviation in WAL effect for higher doping percentage.