Evolution of interlayer tunneling spectra and superfluid density with doping in Bi2Sr2CaCu2O8+delta

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTORS;    INTRINSIC JOSEPHSON-JUNCTIONS;    T-C SUPERCONDUCTORS;    PENETRATION-DEPTH MEASUREMENTS;    NORMAL-STATE PROPERTIES;    MUON SPIN ROTATION;    GRAIN-BOUNDARIES;    SINGLE-CRYSTALS;    OVERDOPED BI2SR2CACU2O8+DELTA;    CUPRATE SUPERCONDUCTORS;   

DOI  :  10.1103/PhysRevB.85.214529

来源: SCIE

【 摘 要 】

Interlayer tunneling spectra, the Josephson critical current density J(c), and the normal tunneling resistance have been measured simultaneously for intrinsic Josephson junctions in Bi2Sr2CaCu2O8+delta over a wide range of doping using a small mesa structure and a short-pulse technique. It is found that J(c) decreases by nearly two orders of magnitude in the underdoped region. Experimental J(c) is found to show a significant deviation from the theoretical estimates. In order to interpret the result, we propose a model in which the superconducting order parameter is inhomogeneous in k space rather than in real space. Based on this model, quasiparticle current-voltage characteristics are calculated, giving a qualitative agreement with the experiment.

【 授权许可】

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