Effect of disorder in the entropy-jump at the first-order vortex phase transition in Bi2Sr2CaCu2O8

M.I. DOLZ; P. PEDRAZZINI; Y. FASANO; M. KONCZYKOWSKI; H. PASTORIZA

S.C. de Bariloche

Conferencia; Advanced Topics of Magnetism and Superconductivity (AToMS-2014); 2014

Centro Atomico Bariloche (CNEA) e Instituto Balseiro (CNEA-UNCuyo)

In this work we study the effect of disorder introduced by heavy-ion irradiation in the thermodynamic magnitudes entailed in the first-order vortex phase transition in the layered Bi2Sr2CaCu2O8 compound. We track the evolution of the enthalpy and the entropy-jump per pancake vortex for this vortex solidification transition by means of AC local magnetic measurements. We study how the density of columnar-track pins affects the temperature evolution of these thermodynamic properties. From this evidence we find that the electro magnetic coupling between pancake vortices lying in adjancent CuO layers plays a dominant role independently of the density of disorder.