Electro−Photo Double Control of Resistive Switching in Electron‐Doped La_0.9Hf_0.1MnO₃ Films

Abstract

Electron‐doped La0.9Hf0.1MnO3 thin films are epitaxially integrated onto 0.7Pb(Mg1/3Nb2/3)O3−0.3PbTiO3 single‐crystalline ferroelectric substrates to construct multiferroic heterostructures. By applying a light field and not just changing temperature, the relative magnitude of the electric‐field‐generated lattice strain effect and interfacial charge effect is identified to be controllable. Moreover, the electric field can enhance the photoresistance effect by 26%. This, accompanied by light‐tunable electroresistance effect, intimate interaction between the electric‐field‐generated and light‐generated effects is demonstrated. Herein, a route to achieve low‐power multifield (light and electric field) control of electronic transport in electron‐doped perovskite manganites is provided.

Effects of electric field and light on resistivity switching of Eu0.7Sr0.3MnO3 thin films

“…1(b). This result is similar to the interfacial charge effect in La 0.9 Hf 0.1 MnO 3 /PMN–PT systems as reported by Liu et al 27 When the temperature and current decrease, e.g. , for T = 270 K and I = 1 μA, the black curve in Fig.…”

“…1(b). This result is similar to the interfacial charge effect in La 0.9 Hf 0.1 MnO 3 /PMN-PT systems as reported by Liu et al 27 When the temperature and current decrease, e.g., for T = 270 K and I = 1 mA, the black curve in Fig. 4(a) shows an antisymmetric graph, indicating that the polarization current effect is the main factor affecting the film resistivity change.…”

“…Wu et al 26 demonstrated the resistive switching behaviors caused by both converse piezoelectric effect and polarization current effect in La 0.67 Ca 0.33 MnO 3 /PMN-PT systems and reported that the lower in-plane reading current, the more obvious the polarization current effect (that is, the polarization current generated by the polarization of ferroelectric single crystal substrate regulates the film resistivity). Except for the electric field or temperature modulation of film resistance, Liu et al 27 also discovered a single photoinduced change from interfacial charge effect to lattice strain effect in the electron-doped La 0.9 Hf 0.1 MnO 3 / PMN-PT system to design multifunctional electronic devices.…”

Polarization current effect, strain effect and ferroelectric field effect on electrical transport properties of Eu0.7Sr0.3MnO3/PMN-PT multiferroic heterostructure

“…We measured the temperature dependence of the thin film resistance when the substrate was in the unpolarized state, as shown in figure 2. Similar to the results observed in the La 0.9 Hf 0.1 MnO 3 film grown on the (001)-oriented PMN-PT substrate [21], the increased impact of interface charge effect at low temperature can be attributed to the localization of charge carriers [22][23][24]. Therefore, as the temperature decreases, the localization of charge carriers makes the resistance of the ESMO film increase with the decrease of temperature, showing typical insulator behavior.…”

“…The heat effect brought by illumination is not taken into consideration. The reason is that the photon energy of the 532 nm light used in the experiment is larger than the band gap of perovskite manganites (1.0-1.3 eV) [21], and the light is absorbed by ESMO thin films, and thus the photoelectric effect is dominant. On the other hand, the sample is placed in a thermostat to maintain a fixed temperature as required throughout the experiment, which helps in controlling and minimizing the influence of other thermal effects.…”