Vortex pinning and vortex channeling in twinned YBa2Cu3O7

G. A. JORGE; E.E. RODRÍGUEZ

Helsinki

Conferencia; 22nd International Conference on Low Temperature Physics; 1999

We analyze the e!ects of correlated disorder on the vortex dynamics in twinned YBa2Cu3O7 crystals by means of susceptibility experiments probing the compression mode of the lattice. When the magnetic "eld is oriented around the direction of the twin boundaries, the shielding (Ds@D) shows a relative maximum or relative minimum amplitude whenHDD c, depending on whether temperature is above or below a well-de"ned ¹#). At ¹´¹#) , the relative maximum manifests vortex pinning by the boundaries, whereas below ¹#) the boundaries may form channel walls for easy paths for vortex #ow and thereby the shielding for HDD c is lower than for other "eld orientations.