The carrier concentration of Tl2Ba2CaCu2O8 films was modified by annealing in N2 gas. X-ray analysis of the structure and the oxygen content revealed a correspondence between carrier concentration and oxygen depletion. The TC and nonlinear surface impedance was measured using a dielectric resonator and the nonlinearity slope parameter r=dXS/dRS was found to converge to unity at the critical temperature, indicating a dominance of Josephson fluxon hysteresis on the nonlinearity. Highly inductive nonlinearity was observed in a small range of doping levels between 0.180<p<0.195 holes/Cu, which does not include the optimal doping level of 0.16 holes/Cu.
@article{arxiv.1310.4158,
title = {Hole Concentration Effect on the Microwave Nonlinearity of Tl2Ba2CaCu2O8-d Superconducting Thin Films},
author = {M. M. Bischak and J. Thomas and R. R. Philip and S. K. Remillard},
journal= {arXiv preprint arXiv:1310.4158},
year = {2014}
}