INVESTIGADORES
HABERKORN Nestor Fabian
congresos y reuniones científicas
Título:
Effect of doping on the crystalline structure and superconductivity properties in Ca(1-x)Na(x)Fe2As2 single crystals
Autor/es:
L. CIVALE; N. HABERKORN; B. MAIOROV; M. JAIME; G. CHEN; W. YU
Lugar:
Dallas
Reunión:
Congreso; APS March Meeting 2011; 2011
Institución organizadora:
American Physical Society
Resumen:
We have studied the crystalline structure and the superconducting
properties
of Ca(1-x)Na(x)Fe2As2 single crystals for various
levels of
the chemical doping (x). We performed a comparative analysis of
the angular
dependent Hc2 for x~0.5 and x ~ 0.75,
corresponding to Tc19 K and 33 K, respectively.
We found that
in both cases Hc2 versus angle near Tc exhibits a single band
character with the same anisotropy gamma ~ 1.8. In
the crystal
with Tc ~ 33 K we detected the presence of a
narrow vortex-liquid
phase, in agreement with the expectation from estimates based on the
Lindemann criterion and the Ginzburg number. We also found large and
anisotropic flux creep rates, with temperature dependences that
indicate
glassy relaxation. We analyzed those results in terms of single
vortex and
collective pinning regimes associated with random and correlated
disorder.
