Direct visualization of local pinning forces in Bi2Sr2CaCu2O8+d vortex matter

ARAGÓN SÁNCHEZ, J.; CORTÉS MALDONADO, R.; DOLZ, M.I.; RUMI, G.; CEJAS BOLECEK, N.R.; KONCZYKOWSKI, M.; NIEVA, G.; PEDRAZZINI, P.; FASANO, Y.

S.C. de Bariloche

Simposio; (SLAFES XXIII) XXIII Latin American Symposium on Solid State Physics; 2018

Centro Atómico Bariloche (CNEA)

We study the local vortex-vortex interaction force, fi, of the vortex state frozen during a field-cooling process in an electron-irradiated Bi2Sr2CaCu2O8+d sample. These local magnitudes are computed from snapshots of the vortex structure obtained via magnetic decoration experiments when field-cooling process at different fields H. Since the observed structures correspond to the equilibrium ones frozen at T~Tirr (H) [4], the local modulus of fi equals the vortex-pinning centers interaction at the sample surface. We estimated the average pinning force fp as a function of H by mapping the local fi . We found that fp grows algebraically with field and is roughly 20% smaller than in the case of the stronger pinning potential generated by irradiation with heavy-ions (columnar defects).