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Topological-metal to band-insulator transition in (Bi(1-x)In(x))2Se3 thin films
Matthew Brahlek1, Namrata Bansal, Nikesh Koirala
1Department of Physics & Astronomy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
Abstract:
By combining transport and photoemission measurements on (Bi(1-x)In(x))(2)Se(3) thin films, we report that this system transforms from a topologically nontrivial metal into a topologically trivial band insulator through three quantum phase transitions. At x ≈ 3%-7%, there is a transition from a topologically nontrivial metal to a trivial metal. At x ≈ 15%, the metal becomes a variable-range-hopping insulator. Finally, above x ≈ 25%, the system becomes a true band insulator with its resistance immeasurably large even at room temperature. This material provides a new venue to investigate topologically tunable physics and devices with seamless gating or tunneling insulators.
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