Инд. авторы: Yoshikawa T., Sumida K., Ishida Y., Chen J., Nurmamat M., Akiba K., Miyake A., Tokunaga M., Kokh K.A., Tereshchenko O.E., Shin S., Kimura A.
Заглавие: Bidirectional surface photovoltage on a topological insulator
Библ. ссылка: Yoshikawa T., Sumida K., Ishida Y., Chen J., Nurmamat M., Akiba K., Miyake A., Tokunaga M., Kokh K.A., Tereshchenko O.E., Shin S., Kimura A. Bidirectional surface photovoltage on a topological insulator // Physical Review B. - 2019. - Vol.100. - Iss. 16. - Art.165311. - ISSN 2469-9950. - EISSN 2469-9969.
Идентиф-ры: DOI: 10.1103/PhysRevB.100.165311; РИНЦ: 41704753; WoS: 000493519900006;
Реферат: eng: 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 >4 mu s. We provide the keys besides the in-gap Fermi level to engineer the SPV on TIs.
Ключевые слова: CONDUCTIVITY; PHOTOCURRENTS; BI2TE3; THERMOELECTRIC POWER; EXPERIMENTAL REALIZATION; PHOTOEMISSION; STATES;
Издано: 2019
Физ. хар-ка: 165311