Abstract
The electrical resistivity and Hall resistivity of have been measured over a wide fluorine-doping range using 60 T pulsed magnets. While the superconducting phase diagram displays the classic dome-shaped structure, we find that the resistive upper critical field increases monotonically with decreasing fluorine concentration, with the largest for . This is reminiscent of the composition dependence in high- cuprates and might correlate with opening of a pseudogap in the underdoped region. Furthermore, the temperature dependence of for superconducting samples can be understood in terms of multiband superconductivity. data for nonsuperconducting samples show nonlinear field dependence, which is also consistent with a multicarrier scenario.
- Received 18 August 2008
DOI:https://doi.org/10.1103/PhysRevB.79.144527
©2009 American Physical Society