Enhancement of resistive switching effect in double-layered Pt/Pr0.7Ca0.3MnO3/La0.6Pr0.4MnO3/SrNb0.01Ti0.99O3 heterostructure

Resistive switching (RS) effect in the double-layered structure of Pt/Pr0.7Ca0.3MnO3 (PCMO)/La0.6Pr0.4MnO3 (LPMO)/SrNb0.01Ti0.99O3 (SNTO) are improved comparing with that in the single-layered structure of Pt/PCMO/SNTO. We propose that the RS characteristics of the two structures depend on the electronic properties of the depletion layer formed in PCMO layer with negative space-charge near the interface of PCMO and LPMO (or SNTO), which should be caused by the migration of oxygen vacancies. Our numerical results show that the negative space-charge region formed in the whole LPMO layer in Pt/PCMO/LPMO/SNTO causes an increase of the electric field, which results in the increase of the number of oxygen vacancies to migrate and thereby improving the RS effect.