Modulation of persistent magnetoresistance by piezo-strain effect in manganite-based heterostructures

Persistent magnetoresistance effects in the phase-separated Pr_0.65(Ca_0.25Sr_0.75)_0.35MnO₃/SrTiO₃ and Pr_0.65(Ca_0.25Sr_0.75)_0.35MnO₃/0.7PbMg_1/3Nb_2/3O₃-0.3PbTiO₃ heterostructures under a low magnetic field are investigated. It is observed that the persistent magnetoresistance effects decrease with increasing temperatures and the values for the heterostructures on 0.7Pb(Mg_1/3Nb_2/3)O₃-0.3PbTiO₃ and SrTiO₃ substrates are about 86.6% and 33.2% at 40 K, respectively. More interestingly, the applied electric field on the 0.7PbMg_1/3Nb_2/3O₃-0.3PbTiO₃ substrate can suppress the persistent magnetoresistance effect, indicating that different energy landscapes can be dramatically modulated by the piezo-strain. These results are discussed in terms of the strain-induced competition in the ferromagnetic state and the charge-ordering phase by the energy scenario, which provide a promising approach for designing devices of electric-magnetic memories in all-oxide heterostructures.