Investigation of spin-polarized carrier injection effect in|YBa2Cu3O7/SrTiO3/La0.67/Sr0.33MnO3 and YBa2Cu3O7/La0.67Sr0.33MnO3 heterostructures

We report preparation and electrical properties of the YBa2Cu3O7SrTiO3(d ≈ 5.0 nm)/La0.67Sr0.33MnO3 (YBCO/STO/LSMO) and YBCO/LSMO multilayer structures grown heteroepitaxially on LaAlO3(100) substrates by single source pulsed injection MOCVD. The heterostructures were patterned in a cross-strip geometry to perform electrical measurements at T=78/300 K under magnetic field μ0H= 0/16 T using 4-probe dc method. Suppression of a supercurrent of the patterned YBCO stripes was indicated for the YBCO/LSMO heterostructure by injecting tunneling spin-polarized current fiom the underlying FM layer. The transport effects were modelled taking into account current redistribution in the adjacent conducting HTS and FM layers