Abstract
Measurements of the nonlinear complex susceptibility x, taken as a function of amplitude h and frequency n of the ac field, can collapse into a single universal curve if they are plotted against the scaling variable hJ(n re f)/J(n), where J is a shielding current density and n re f is an arbitrary reference frequency. In this work we present x(h,n) data for a large range of amplitudes and frequencies, measured in two Nb samples ~one single crystal and one polycrystal! and one melt-textured YBa2Cu3O72d sample. The predicted scaling relation is verified for several sets of data taken at different temperatures below Tc and applied magnetic fields well above the first critical fieldHc1. Data taken closer to Tc revealed a useful scaling applied directly to the critical current density, evaluated from the peak positions of the imaginary component x9. The occurrence of different regimes of collective vortex creep is also discussed for the YBa2Cu3O72d sample.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
