title: In-plane topological p-n junction in the three-dimensional topological insulator Bi2-xSbxTe3-ySey.
abstract: A topological p-n junction (TPNJ) is an important concept to control spin and charge transport on a surface of three-dimensional topological insulators (3D-TIs). Here we report successful fabrication of such TPNJ on a surface of 3D-TI Bi2-xSbxTe3-ySeythin films and experimental observation of the electrical transport. By tuning the chemical potential of n-type topological Dirac surface of Bi2-xSbxTe3-ySeyon its top half by using tetrafluoro-7,7,8,8-tetracyanoquinodimethane as an organic acceptor molecule, a half surface can be converted to p-type with leaving the other half side as the opposite n-type, and consequently TPNJ can be created. By sweeping the back-gate voltage in the field effect transistor structure, the TPNJ was controlled both on the bottom and the top surfaces. A dramatic change in electrical transport observed at the TPNJ on 3D-TI thin films promises novel spin and charge transport of 3D-TIs for future spintronics.
authors.affiliation: Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
authors.forename: Ngoc Han
authors.initials: NH
authors.lastname: Tu
authors.affiliation: Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tanabe
authors.affiliation: Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Satake
authors.affiliation: WPI-Advanced Institute for Materials Research, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
authors.forename: Khuong Kim
authors.initials: KK
authors.lastname: Huynh
authors.affiliation: Department of Physics, Graduate School of Science, Tohoku University, 6-3 Aramaki, Aoba-ku, Sendai, Miyagi 980-8577, Japan.|WPI-Advanced Institute for Materials Research, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
authors.forename: Katsumi
authors.identifier: 0000-0002-2293-0079
authors.initials: K
authors.lastname: Tanigaki