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The Extremely Enhanced Photocurrent Response in Topological Insulator Nanosheets with High Conductance.

ABSTRACT: The photocurrent was performed in topological insulator nanosheets with different conductances. The higher photocurrent is observed in the nanosheet with higher conductance. The responsivity is proportional to the nanosheet conductance over two orders. The responsivity is independent of the light power intensity in vacuum, but responsivity drastically decreases at low power intensity in air. The ratio of the responsivity in air to that in vacuum is negatively proportional to the the inverse of the light power intensity. These behaviors are understood as the statistical photocurrent in a system with blocked molecules. The time constant decreases as the thickness increases. A longer time constant is observed in lower atmosphere pressure.

SUBMITTER: Huang SM

PROVIDER: S-EPMC6249153 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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The Extremely Enhanced Photocurrent Response in Topological Insulator Nanosheets with High Conductance.

Huang Shiu-Ming SM Lin Lin-Jie LJ Yan You-Jhih YJ Yu Shih-Hsun SH Chou Mitch M C MMC Hsieh Ho-Feng HF Ho Chin-Jung CJ Chen Ruei-San RS

Nanoscale research letters 20181121 1

The photocurrent was performed in topological insulator nanosheets with different conductances. The higher photocurrent is observed in the nanosheet with higher conductance. The responsivity is proportional to the nanosheet conductance over two orders. The responsivity is independent of the light power intensity in vacuum, but responsivity drastically decreases at low power intensity in air. The ratio of the responsivity in air to that in vacuum is negatively proportional to the the inverse of t ...[more]

PMID: 30465297

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