Tunable multiferroic and bistable/complementary resistive switching properties of dilutely Li-doped BiFeO3 nanoparticles: an effect of aliovalent substitution

Abstract

We report a potential way to enhance and tune the multiferroic and resistive switching properties of BiFeO₃ nanoparticles through dilute aliovalent Li¹⁺ doping (0.046 atomic percent) at the Fe³⁺ sites of BiFeO₃. The high purity of the samples and the extent of doping were confirmed by different physical characterizations. Enhanced multiferroic properties with a magnetic moment per Fe atom ≈ 0.12 μ_B and electric polarization ≈ 49 μC cm⁻² were observed in one of the Li¹⁺ doped samples. A phenomenological model has been proposed to support the observed magnetic behavior of the doped samples. From a potential application point of view, we further report on the doping concentration and polarization coercivity dependent highly stable resistive switching behavior (endurance cycles >10³ and stability >10⁶ s) of Li-doped BiFeO₃ nanoparticles. The stable complementary resistive switching behavior (1 bit operation) for >50 cycles and under voltage pulse for 10³ cycles in the doped BiFeO₃ at a low operating bias is reported. Thus, dilute aliovalent Li¹⁺ doping enables tunability of the ferroic and resistive switching properties of BiFeO₃and shows it to be a promising multiferroic material.