Formation of two layers in Pr1-xCaxBa2Cu3O7-y (0 <= x <= 0.5) thin films deposited at different temperatures

We have grown epitaxial Pr1-xCaxBa2Cu3O7-y (0 less than or equal to x less than or equal to 0.5) thin films on SrTiO3 and Yttrium stabilized zirconia (YSZ) substrates by pulsed laser deposition at different temperatures. X-ra y diffraction and transmission electron microscopy analysis revealed epitax ial growth on YSZ substrates for x = 0 along the a and c axis directions fo r T = 570 degrees C, where first the film grows oriented along a-axis and a fterward, it undergoes a shift in the orientation, growing in the c-axis di rection from then on. The cell parameters were c = 1.166 nm and a similar t o 6 = 0.386 nm.