Exchange biasing in La2/3Ca1/3MnO3/La1/3Ca2/3MnO3 multilayers

A series of [La2/3Ca1/3MnO3/La1/3Ca2/3MnO3](15) multilayers, with bilayer t hicknesses between 2 and 32 nm, has been prepared by pulsed laser depositio n. The study of their magnetic and magnetotransport properties reveals, for the first time in this category of materials, the presence of an exchange biasing mechanism at low temperatures. Zero-field-cooling and field-cooling magnetic measurements reveal a blocking temperature around 70 K that is in dependent of the bilayer thickness, whereas the average film magnetization becomes zero at 250 K. (C) 1999 American Institute of Physics. [S0021-8979( 99)27408-7].