Persistent photoconductivity in overdoped high-Tc thin films
نویسندگان
چکیده
Overdoped Tl 2Ba 2CuO 61d exhibits persistent photoconductivity at low temperatures. This effect has been observed before only in underdoped RBa 2Cu 3O 72d (R5rare earth or yttrium!. Contrary to RBa 2Cu 3O 72d , Tl 2Ba 2CuO 61d shows either a persistent increase or decrease of the carrier density with illumination, depending on doping and wavelength of the incident light. Thus it is possible to increase or decrease the superconducting transition temperature in Tl 2Ba 2CuO 61d reversibly. These photoinduced changes can be explained by the existence of localized states in the charge reservoir layer. @S0163-1829~97!06046-3#
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تاریخ انتشار 1997