Influence of magnetic (Fe) and non-magnetic (In) doping on structural, magnetic, and weak anti-localization properties of Bi2Te3 topological insulator

Abstract

In this article, we have studied the changes in structural, magnetic, and magneto-transport properties of Bi2Te3 topological insulator doped with magnetic (Fe) as well as non-magnetic (In) elements. The un-doped along with Fe, In-doped Bi2Te3 are grown using a melt growth technique. The Rietveld analysis of x-ray diffraction data expresses that both In and Fe-dopants substituted the Bi-position with a little bit of interstitial incorporation in host Bi2Te3. It is also noticed that In-doping is slightly more favorable for Bi-substitution than Fe. The magnetic characterization reveals a mixing of diamagnetic and Pauli paramagnetic behavior of un-doped and In-doped Bi2Te3, whereas, Fe-doping shows overall paramagnetism with local anti-ferromagnetic interactions among Fe-ions without long-range order. The electrical-transport study represents the metallic response of host Bi2Te3, which is well-maintained for In-doping; however, Fe-doping exhibits prominent anomalies in ρ xx -T profiles. Importantly, magneto-conductance research indicates a notable deviation of host quantum feature, weak anti-localization effect (WAL) upon magnetic (Fe) doping, whereas non-magnetic In-doping shows a comparatively weak deviation in WAL effect for high doping limit.