Reversible Resistance Switching In La0.225pr0.4ca0.375mno3: The Joule-Heat-Assisted Phase Transition

The reversible resistance switching (RS) controlled by current pulse pairs, accompanied with an overshooting relaxation, is observed in bulk La0.225Pr0.4Ca0.375MnO3. We demonstrate that the reversible RS effect is not the result of current-induced intrinsic transition of charge-ordered insulator (COI) into ferromagnetic metal (FMM) phase, but the outcome of Joule-heat-assisted transition between the FMM and COI phases. A local thermal-cycle assisted rearrangement of the FMM phase in the COI matrix is controllable by a current pulse, opening a possibility for multistate memory applications. (C) 2009 American Institute of Physics. [doi:10.1063/1.3241997]