Universal scaling of the c -axis dc conductivity for underdoped high-temperature cuprate superconductors

• Published in: Solid state communications 2010-12, Vol.150 (47), p.2314-2317
• Main Authors: Honma, T., Hor, P.H.
• Format: Article
• Language: English
• Subjects: A. High- [formula omitted] cuprates; Blocking; Condensed matter: electronic structure, electrical, magnetic, and optical properties; COPPER OXIDE; Cuprates; D. Universal scaling; Direct current; DOPING; E. Out-of-plane dc conductivity; ELECTRICAL CONDUCTIVITY; Exact sciences and technology; Optimization; Physics; Properties of type I and type II superconductors; Solid state; SOLID STATE PHYSICS; Superconductivity; SUPERCONDUCTORS; Transport; Transport properties (electric and thermal conductivity, thermoelectric effects, etc.)
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2010.10.003

The coexistence of ‘metallic-like’ in-plane dc conductivity and ‘semiconducting-like’ out-of-plane ( c -axis) dc conductivity ( σ c ) , generating huge anisotropy in underdoped high-temperature cuprate superconductors (HTCSs), defies our current understanding of metals. In this report, we present an intrinsic doping dependence of σ c . We find that σ c for underdoped HTCSs is universally scaled to the σ c value at the optimal doped-hole concentration. The universal scaling behavior suggests that there are three intrinsic processes that contribute to σ c : (i) the doping-dependent-activated gap; (ii) the exponential doping dependences, and (iii) the tunneling between adjacent CuO 2 block layers. They are the essential underlying characteristics of the c -axis transport for all HTCSs.