[摘要]：The top and bottom electrodes of the ferromagnetic manganite La0.7Ca0.3MnO3 may be magnetically decoupled by a La0.59Ca0.41MnO3 interlayer in which ferromagnetic and paramagnetic phases coexist. In mesas fabricated from these trilayer films, in-plane magnetic domain walls associated with the antiparallel magnetic electrode configuration show a giant resistance-area product > 10(-10) Omega m(2). This is almost two orders of magnitude larger than our devices with interlayer composition La0.6Ca0.4MnO3 [C. Israel et al., Phys. Rev. B 78, 054409 (2008)] where phase separation is less extreme. High-field treatments modify the ferromagnetic phase fraction of the interlayer. (C) 2010 American Institute of Physics. [doi:10.1063/1.3527942]
