Magneto-Transport Properties of Insulating Bulk States in Bi(111) Films

Abstract

Magneto-transport properties of insulating bulk states in Bi(111) films are systematically investigated under the parallel field (𝐵 ‖ ). We find that the magnetotransport of the 𝐵 ‖ field is a more powerful tool to distinguish the bulk states and the surface states. A large magnetoresistance (MR) up to 20% in the 𝐵 ‖ field is induced by the insulating bulk states for the suppression of the backward scattering. With the increasing thickness, a positive MR(𝐵 ‖ ) from magnetic induced boundary scattering appears in the semimetal films. As the thickness is reduced to 10 nm, the positive MR(𝐵 ‖ ) is induced by weak anti-localization from the surface states.