Quantum Resistive Behaviors in Vortex Liquid Regimes at Finite Temperatures

Motivated by a mean field-like resistive behavior in magnetic fields commonly seen in various superconducting cuprates and organics with strong fluctuation, superconducting (SC) quantum fluctuation effects on resistive behaviors are reexamined by putting emphasis on their roles in the so-called thermal vortex liquid regime. By incorporating the quantum fluctuations and a vortex pinning effect in the Ginzburg-Landau (GL) fluctuation theory, it is found that the resistivity ρ(T )-curve sharply drops, with no fan-shaped broadening, at a vortex-glass transition point far below an apparent upper critical field H∗ c2(T ) as a result of a quantum fluctuation enhanced by an adequately small condensation energy or by a strong field. Fittings to ρ-T data of cuprates and organics are performed by phenomenologically including a SC pseudogap region created by high energy SC fluctuations and possible fluctuations of competing non-SC orders. By examining La2−xSrxCuO4 data over a broad doping range, we obtain such conclusions, consistent with recent experimental results, that the inplane coherence length of hole-doped cuprates decreases with approaching the underdoped limit even in the presence of fluctuating competing orders and that the condensation energy density (Hc(0)) 2 = 0.5[φ0/(2πλ(0)ξ0)] 2 is maximal near the optimal doping. Further, the case of disordered quasi 2D films showing the field-tuned superconductor-insulator transition is also examined for comparison and discussed in relation to data reported recently.