Comparative study of magnetic and electric field induced insulator-metal-transitions in Pr<Subscript>1-x</Subscript>Ca<Subscript>x</Subscript>MnO<Subscript>3</Subscript> films

The insulator-metal (IM)-transition in Pr<Subscript>1-x</Subscript>Ca<Subscript>x</Subscript>MnO<Subscript>3</Sub script> (PCMO) is of particular interest because it can be induced by a variety of external forces, such as magnetic and electric fields, photon exposure and hydrostatic pressure. In this paper, we present a comparative study of the IM-transition in magnetic and electric fields for epitaxial thin films prepared by pulsed laser deposition. The transport data as a function of applied field or temperature give strong evidence for the presence of electronic phase separation. However, the observed different IM-transitions in magnetic and electric fields indicate that two different areas of spatially inhomogeneous electronic ground states in the phase diagram of PCMO are involved. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006