Hall Effect in CLBLCO Superconductors

Electrical charge transport carrier concentration trends were observed with Hall effect experiments in (Ca$_{x}$La$_{1-x})$(Ba$_{1.75-x}$La$_{0.25+x})$Cu$_{3}$O$_{y}$. All values of x yield similar trends in R$_{H}$ vs. T, but increasing doping (y) reduces R$_{H}$ as expected. All samples that exhibit superconductivity (SC) also exhibit a maximum Hall coefficient at approximately 2T$_{C}$. Contrarily, in the extreme doping cases (non SC samples) no maxima are observed and the underdoped cases exhibit insulator-like increased R$_{H}$ at lower T. A full description of experiment and analysis will be presented.