Author:

Keywords:

high-temperature superconductors, density-of-states, electron-vortex scattering, high-tc superconductors, ba-cu-o, mixed-state, thermoelectric-power, resistive transition, field, dependence, Science & Technology, Physical Sciences, Physics, Applied, Physics, Condensed Matter, Physics, HIGH-TEMPERATURE SUPERCONDUCTORS, DENSITY-OF-STATES, ELECTRON-VORTEX SCATTERING, HIGH-TC SUPERCONDUCTORS, BA-CU-O, MIXED-STATE, THERMOELECTRIC-POWER, RESISTIVE TRANSITION, FIELD, DEPENDENCE, 0204 Condensed Matter Physics, 0906 Electrical and Electronic Engineering, 0912 Materials Engineering, General Physics, 4016 Materials engineering, 5104 Condensed matter physics

Abstract:

Various physical properties of a high-pressure made Bi1.84Pb0.34Sr1.91Ca2.03Cu3.06Ox ceramic have been studied in the normal state and mixed state region, mainly from the point of view of transport properties. The electrical resistivity, the thermoelectric power and the Nernst effect are reported for a broad temperature range and for fields between 0 and 4 T. Derived physical parameters like the excess (integrated) properties, the behaviour of the percolation line(s) as a function of temperature and field, the so-called transport energy, and the so-called activation energies, the Ginzburg-Landau parameter and the thermal Hall angle field and temperature dependence are given and briefly compared with previous reports. We point out that in the region examined, the so-called percolation lines differ whether the transport coefficient is purely electrical or is electrothermal in nature. We point out that the 90 degrees thermal Hall angle temperature is the same as the thermoelectric percolation temperature. Finally we examine for the first time in such systems the behaviour of the so-called 'electrothermal conductivity'. Through a kinetic formalism using either an s-wave or a d-wave-like order parameter, we point out that the field dependence is quite different in the mixed state near the critical temperature. This allowed us to decide that the signature for a d-wave nature of the gap parameter exists for such transport properties near the critical temperature.