@article{538021f788944c299305cb5d546a8a8c,
title = "Bidirectional surface photovoltage on a topological insulator",
abstract = "Controlled extraction of spin-polarized currents from the surface of topological insulators (TIs) would be an important step to use TIs as spin-electronic device materials. One way is to utilize the surface photovoltage (SPV) effect, by which the surface current may flow upon irradiation of light. To date, unipolar SPV has been observed on TIs, while the realization of ambipolar SPV is crucial for taking control over the direction of the flow. By using time-resolved photoemission, we demonstrate the ambipolar SPV realized on the TI Bi2Te3. The topological surface states showed downward and upward photovoltaic shifts for the n- and p-type samples, respectively. We also discerned the photogenerated carriers accumulated in the surface states for >4μs. We provide the keys besides the in-gap Fermi level to engineer the SPV on TIs.",
author = "T. Yoshikawa and K. Sumida and Y. Ishida and J. Chen and M. Nurmamat and K. Akiba and A. Miyake and M. Tokunaga and Kokh, {K. A.} and Tereshchenko, {O. E.} and S. Shin and A. Kimura",
note = "Funding Information: The experiments were performed at ISSP, University of Tokyo. This work was partly supported by the Bilateral Collaboration Program between RFBR (Russia) and JSPS (Japan) and also by KAKENHI Grants No. 26247064, No. 26800165, No. 17H06138, No. 18H01148, No. 18H03683, and No. 19H00651. This study was also supported by the Saint Petersburg State University (Grant No. 15.61.202.2015) and the Russian Science Foundation (Project No. 17-12-01047) in part of the single-crystal growth and structural characterization. K.A.K. was financially supported by RFBR (Grant No. 18-29-12094) and state assignment contract of IGM SB RAS. T.Y. and K.S. were financially supported by the Grant-in-Aid for JSPS Fellows No. 18J22309 and No. 19J00858, respectively. Publisher Copyright: {\textcopyright} 2019 American Physical Society.",
year = "2019",
month = oct,
day = "31",
doi = "10.1103/PhysRevB.100.165311",
language = "English",
volume = "100",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "16",
}