Nonlinear current-voltage behavior and electrically driven phase transition in charge-frustrated LuFe2O4L. J. Zeng1, H. X. Yang1, Y. Zhang1, H. F. Tian2, C. Ma1, Y. B. Qin1, Y. G. Zhao2 and J. Q. Li1
1 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences - Beijing 100190, PRC
2 Department of Physics, Tsinghua University - Beijing 100084, PRC
received 18 September 2008; accepted in final form 3 November 2008; published December 2008
published online 16 December 2008
Electric transport measurements of the charge-frustrated LuFe2O4, in which charge ordering (CO) and electronic ferroelectricity are found, reveal a strong nonlinear electric conduction upon application of electric fields in both single-crystalline and polycrystalline samples. The threshold electric fields in LuFe2O4 are estimated to be about 60 V/cm and 10 V/cm with E parallel and perpendicular to the c-axis direction, respectively. Experimental measurements also demonstrate that the I-V nonlinearity increases quickly with decreasing temperature. Furthermore, our in situ TEM investigations clearly reveal that the nonlinear I-V behavior is intrinsically in correlation with a current-driven charge ordering insulator-metal transition, and the applied electrical field triggers a visible CO collapse recognizable as the fading of the satellite spots of the CO modulations.
71.27.+a - Strongly correlated electron systems; heavy fermions.
71.30.+h - Metal-insulator transitions and other electronic transitions.
61.05.J- - Electron diffraction and scattering.
© EPLA 2008