Unusual Charge Localization in Zn-doped and Heavily Underdoped YBa2Cu3O7−δ at Low Temperatures
نویسندگان
چکیده
The in-plane normal-state resistivity of Zn-doped YBa2Cu3O7−δ and heavily underdoped pure YBCO single crystals is measured down to low temperatures under magnetic fields up to 18 T. We found that the temperature dependence of the normal-state ρab does not obey log(1/T ) and tends not to diverge in the low temperature limit. The result suggests that the “ground state” of the normal state of YBCO is metallic. PACS numbers: 74.25.Fy, 74.62.Dh, 74.72.Bk
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