APS Logo

Pb-doped p-type Bi<sub>2</sub>Se<sub>3</sub> thin films via interfacial engineering

ORAL

Abstract

Due to high density of native defects, the prototypical topological insulator, Bi2Se3, is naturally n-type. Although Bi2Se3 can be converted into p-type by substituting 2+ ions for Bi, only light elements such as Ca have been so far effective as the compensation dopant. Considering that strong spin-orbit coupling (SOC) is essential for the topological surface states, a light element is undesirable as a dopant, because it weakens the strength of SOC. In this sense, Pb, which is the heaviest 2+ ion, located right next to Bi in the periodic table, is the most ideal p-type dopant for Bi2Se3. However, Pb-doping has so far failed to achieve p-type Bi2Se3 not only in thin films but also in bulk crystals. Here, by utilizing an interface engineering scheme, we have achieved the first Pb-doped p-type Bi2Se3 thin films. Furthermore, at heavy Pb-doping, the mobility turns out to be substantially higher than that of Ca-doped samples, indicating that Pb is a less disruptive dopant than Ca.

–

Presenters

  • Jisoo Moon

    Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Rutgers University, New Brunswick, Department of Physics & Astronomy, Rutgers, The State University of New Jersey

Authors

  • Jisoo Moon

    Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Rutgers University, New Brunswick, Department of Physics & Astronomy, Rutgers, The State University of New Jersey

  • Zengle Huang

    Department of Physics and Astronomy, Rutgers, The State University of New Jersey

  • Weida Wu

    Physics and Astronomy, Rutgers University, New Brunswick, Department of Physics and Astronomy, Rutgers University, Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Department of Physics and Astronomy, Rutgers University, New Brunswick, Rutgers University, New Brunswick

  • Seongshik Oh

    Physics, Rutgers University, Department of Physics and Astronomy, Rutgers University, Department of Physics and Astronomy, Rutgers, the state university of New Jersey, Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Rutgers University, New Brunswick, Department of Physics & Astronomy, Rutgers, The State University of New Jersey