Observation of quantum oscillations in FIB fabricated nanowires of   topological insulator (Bi2Se3)
  Since last few years, research based on topological insulators (TI) is in great interests due to intrinsic exotic fundamental properties and future potential applications such as quantum computers or spintronics. The fabrication of TI nanodevices and study on their transport properties mostly focused on high quality crystalline nanowires or nanoribbons. Here we report robust approach of Bi2Se3 nanowire formation from deposited flakes using ion beam milling method. The fabricated Bi2Se3 nanowire devices have been employed to investigate the robustness of topological surface state (TSS) to gallium ion doping and any deformation in the material due to fabrication tools. We report the quantum oscillations in magnetoresistance curves under the parallel magnetic field. The resistance versus magnetic field curves have been studied and compared with Aharonov-Bohm (AB) interference effects which further demonstrate the transport through TSS. The fabrication route and observed electronic transport properties indicate clear quantum oscillations and can be exploited further in studying the exotic electronic properties associated with TI based nanodevices. 
Biplab Bhattacharyya, Alka Sharma, V P S Awana, A. K. Srivastava, T.   D. Senguttuvan, and Sudhir Husale
cond-mat.mtrl-sci