Surface characterization and magneto-transport study on Bi2Te2Se topological insulator thin film.

Topological insulators (TIs) a new quantum state of matter predicted to have an interesting surface properties. In this report, we study the surface properties of Bi 2 Te 2 Se (BTS) topological insulators thin films. Raman measurements on BTS thin film show a strong intensity of A 1 1 g ( ∼ 62 cm - 1 ), E 2 g ( ∼ 123 cm - 1 ) and A 2 1 g ( ∼ 170 cm - 1 ) modes in addition to A 2 1 u ( ∼ 140 cm - 1 ) modes. Elemental analyses were done using X-ray photoelectron spectroscopy (XPS). Resistance versus temperature measurement reveal a magnetic field-driven metallic behavior at high temperatures and further analysis on magnetic measurement shows a diamagnetic nature of BTS film. The magneto-resistance measurements on these films exhibit a weak antilocalization effect that arises due to quantum interfering nature of topological insulators and the measured weak anti-localization effect is fitted using Hikami–Larkin–Nagaoka (HLN) model. [ABSTRACT FROM AUTHOR]