Additional Evidence for the Surface Origin of the Peculiar
Angular-Dependent Magnetoresistance Oscillations Discovered in a Topological
Insulator Bi_{1-x}Sb_{x}
We present detailed data on the unusual angular-dependent magnetoresistance
oscillation phenomenon recently discovered in a topological insulator
Bi_{0.91}Sb_{0.09}. Direct comparison of the data taken before and after
etching the sample surface gives compelling evidence that this phenomenon is
essentially originating from a surface state. The symmetry of the oscillations
suggests that it probably comes from the (111) plane, and obviously a new
mechanism, such as a coupling between the surface and the bulk states, is
responsible for this intriguing phenomenon in topological insulators.Comment: 5 pages, 4 figures, Proceedings manuscript for the 19th International
Conference on the Application of High Magnetic Fields in Semiconductor
Physics and Nanotechnology (HMF-19