Current-induced Electroresistance Research Articles

The current-induced electroresistance in strain-modulated Pr0.5Sr0.5MnO3 film

Pr0.5Sr0.5MnO3 films were grown on ferroelectric substrates of 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 by pulsed-laser deposition method. The film structure and lattice change with electric field applied on the substrate are examined by X-ray diffraction. The electric field dependence of resistivity was compared with electric field dependence of lattice at room temperature, revealing a relation between resistance and strain. Current-induced electroresistance (CER) was studied by using different measuring current. With increasing electric filed a colossal decrease of CER at low temperature was achieved, indicating great strain effect. The piezoelectric strain effect on the magnetoelectric coupling at multiferroic interface was discussed.

Magnetoresistance and current-induced electroresistance of the Ag/La0.67Ca0.33MnO3interface

Magnetoresistance and current-induced electroresistance of the Ag/La_0.67Ca_0.33MnO₃interface

Current-induced electroresistance in tetravalent cation-doped La 0.9Hf 0.1MnO 3 epitaxial thin films

Influence of electric currents with a high density on the transport behavior of La 0.9Hf 0.1MnO 3 thin films has been investigated in the absence of magnetic field. With different dc-currents from I = 0.5 mA (current density J = 1.0 × 10 3 A/cm 2) to 25.0 mA ( J = 4.8 × 10 4 A/cm 2) applied on the sample, a striking observation is the significant decrease of the metal-insulator transition peak. The observed reduction ratio, the electroresistance ER = [ R(0) − R(I)]/ R(I) is ∼20%. This observation is similar to what we observed in other CMR systems like La 1− x Ca x MnO 3 and La 1− x Ba x MnO 3, indicating that the current-induced ER is a common feature for the CMR materials. The introduced new state is metastable and can be well repeated. Experiments revealed that it is not caused by oxygen deficiency. Although the nature behind such an effect has not been well understood yet, the observed ER effect seems to favor a percolative phase separation picture.

Current-induced effects in La0.9Sr0.1MnO3 film

La0.9Sr0.1MnO3 film has been fabricated on (100) LaAlO3 by direct-current magnetron sputtering. The quality of the film is good as monitored by atom force microscopy and X-ray diffraction. The resistivity-temperature curve shows that the film undergoes metal-insulator transition at 281 K. The peak resistivity decreases with increasing current and the current-induced electro-resistance is 30.5% at 4 mA. The results are simply explained by phase-separation theory.

Anisotropic current-induced electroresistance effect in low-doped La 0.9Sr 0.1MnO 3 thin films

We have studied the giant negative electroresistance (ER) in strips and pillars of single-layer La 0.9Sr 0.1MnO 3 films fabricated by micro-fabrication patterning processes, and observed the different voltage–current ( V– I) characteristics under current-in-plane (CIP) and current-perpendicular-to-plane (CPP) measurement modes, around room temperature. For the CIP mode, V– I curves show an asymmetry with jumps at the negative bias currents, while a symmetrical hysteresis against the polarity for the CPP one. The mechanism is illuminated in the letter. Furthermore, a large ER is obtained for both modes and the ER ratios increase monotonically with the temperature and bias current, suggestive of a promising potential in future device developments.

Strain effect and current-induced electroresistance in epitaxial thin films of La 0.9Sr 0.1MnO 3

La 0.9Sr 0.1MnO 3 thin films with the thickness ranging from 10 to 100 nm have been fabricated by pulsed laser deposition. An insulator-metal transition can be developed with decreasing the thickness of film. The strain compression of the lattice induced by substrate may strongly influence the static Jahn-Teller distortion and cause an increase of double exchange interaction. Subsequently, attention was focused on the influence of a dc current on the resistance of these epitaxial thin films in the absence of a magnetic field. A significant reduction of the peak resistances reaches ∼4% and ∼42% for two samples with different thicknesses upon a current density up to 100 KA/cm 2, respectively. The influence of strain effect on the electrical transport was studied. The strain may stabilize the multiphase coexistence and then suppress the current-induced electroresistance in the system.

Unusual current-induced electroresistance in epitaxial thin films ofLa0.8Ca0.2MnO3

The transport behavior of ${\text{La}}_{0.8}{\text{Ca}}_{0.2}{\text{MnO}}_{3}$ thin films with Curie temperature ${T}_{\mathrm{C}}$ at $\ensuremath{\sim}286\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ has been investigated under various applied currents in the absence of magnetic field. An unusual current-induced electroresistance (ER) was observed. When the applied current density reaches a critical value, the films could not revert to the initial state. A novel state can be induced by a suitable large current, in which the insulation-metal transition temperature remains almost unchanged comparing with the initial state, whereas the value of the peak resistance is very sensitive to the applied current. Even a rather low current density can depress it significantly. ER reaches $\ensuremath{\sim}43%$ under a small current of $0.5\phantom{\rule{0.3em}{0ex}}\text{mA}$ (density $\ensuremath{\sim}1\ifmmode\times\else\texttimes\fi{}{10}^{4}\phantom{\rule{0.3em}{0ex}}\mathrm{A}\phantom{\rule{0.3em}{0ex}}{\text{cm}}^{\ensuremath{-}2}$). The observed ER effect seems to favor a percolative phase separation picture.