Glasslike behavior at the PrBa₂Cu₃O₇∕La_0.75Sr_0.25MnO₃ interface

We study the crystalline structure and the magnetic properties of two different PrBa₂Cu₃O_7−δ∕La_0.75Sr_0.25MnO₃ (PBCO∕LSr_0.25MO) superlattices grown by dc magnetron sputtering on (100) SrTiO₃. The microstructure was studied by high-resolution transmission electron microscopy (HRTEM). Magnetic, magnetotransport, and time dependence measurements indicate a behavior compatible with phase separation at the interface, strain induced by the lattice parameter difference, and the presence of a structural transition in the manganite material. Spin glasslike blocking behavior was found at low temperatures, below 70 K.