The effect of Fe-doping on structural, elemental, magnetic, and weak anti-localization properties of Bi2Se3 topological insulator.

Bi2Se3 has drawn great attention in current research for its novel topological property. In this literature, we establish the variation in structural, elemental, magnetic, and magneto-transport properties of Bi2Se3 due to the influence of Fe-doping. A solid-state synthesis mechanism has been used for the preparation of doped and un-doped Bi2Se3. Rietveld refinement of XRD data reveals the existence of Bi-substitution by Fe for low doping concentration. However, for high Fe-doping, there exists substitution of Bi as well as interstitial incorporation of Fe in host Bi2Se3. The XPS and SEM–EDX analysis also justify that Fe enters substitutionally for Bi and interstitial positions. From the magnetism study we have claimed that Fe-doped Bi2Se3 shows paramagnetism globally with local anti-ferromagnetism among Fe-dopants without long-range magnetic order. Based on electrical-transport survey we notice an increment of residual resistivity ( ρ 0) along with prominent anomaly in ρ xx –T profile around 120 K for high Fe-doping signifies the increment of carriers scattering. More importantly, there exists a gradual deviation of host quantum character, weak anti-localization (WAL) effect upon magnetic Fe-doping through the evidence of magneto-transport analysis. [ABSTRACT FROM AUTHOR]