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Using persistent photoconductivity to write a low-resistance path in SrTiO₃.

ABSTRACT: Materials with persistent photoconductivity (PPC) experience an increase in conductivity upon exposure to light that persists after the light is turned off. Although researchers have shown that this phenomenon could be exploited for novel memory storage devices, low temperatures (below 180?K) were required. In the present work, two-point resistance measurements were performed on annealed strontium titanate (SrTiO₃, or STO) single crystals at room temperature. After illumination with sub-gap light, the resistance decreased by three orders of magnitude. This markedly enhanced conductivity persisted for several days in the dark. Results from IR spectroscopy, electrical measurements, and exposure to a 405?nm laser suggest that contact resistance plays an important role. The laser was then used as an "optical pen" to write a low-resistance path between two contacts, demonstrating the feasibility of optically defined, transparent electronics.

SUBMITTER: Poole VM

PROVIDER: S-EPMC5532236 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Using persistent photoconductivity to write a low-resistance path in SrTiO3.

Poole Violet M VM Jokela Slade J SJ McCluskey Matthew D MD

Scientific reports 20170727 1

Materials with persistent photoconductivity (PPC) experience an increase in conductivity upon exposure to light that persists after the light is turned off. Although researchers have shown that this phenomenon could be exploited for novel memory storage devices, low temperatures (below 180 K) were required. In the present work, two-point resistance measurements were performed on annealed strontium titanate (SrTiO3, or STO) single crystals at room temperature. After illumination with s ...[more]

PMID: 28751708

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