Influence of Y211 particles on the structure of {110} twins in single-grain YBCO

bulk superconductors was studied by polarization light optical microscopy on the

surfaces with small declination from the {110} plane. Used conditions allowed the

observation of twin structure and twin spacing measurements at the twin spacing

below the resolution limit of optical microscopy. Obtained results showed that the

twin spacing was proportional to the square root of the mean free distance between

Y211 particles present in the samples. It was also shown that the twin complex size

can be enormously high under the influence of thermal residual stresses.

Influence of 211 Particles on Twin Spacing in Top-Seeded Melt-Growth YBCO

Bulk Superconductors. P.Diko, D.Šuster: Journal of Applied Physics, 2009, 105[6],

063503