Persistent photoinduced superconductivity
نویسندگان
چکیده
We review work done at UCSD on persistent photoconductivity and photoinduced superconductivity in REBa,Cu~O, thin films. It is shown that the resistivity, Hall coefficient and c-axis parameter change significantly upon illumination. All these effects require the presence of oxygen vacancies. The maximum enhancement of the conductivity with illumination occurs for fully deoxygenated ,samples (x=6.0). The spectral dependence of the persistent photoconductivity has a pronounced peak in the UV region at ,~4.1 eV. All the~ observations can be understood qualitatively with a model based on the trapping of photoexcited electrons at oxygen vacancies in the Cu-O chains of REBa.,Cu.~O,.
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