The electrical transport characterization of dual-layer perovskite, La1.4Sr1.6Mn2O7(327), has been systematically studied by the complex impedance technique. The complex resistivity spectra, under a dc bias (Vdc) from 0 to 400 mV, have been analyzed by an equivalent circuit model (ECM), including a resistance (R) component and two sets of parallel R and capacitance (C) components in series. The electrical elements represent the 327 grain and 327 two different (extrinsic and intrinsic) grain boundaries (GBs) contributions, respectively. The analyzing results by the ECM demonstrate the R decreases, but C increases with rising Vdcfor extrinsic phase of 327 GBs. The behavior can be assigned to the trap-states dominated conduction. For intrinsic phase of 327 GBs, R is almost independent on the Vdc but C decreases with rising Vdc, The transport behavior can be attributed to the decrease of electric dipoles rotation by increasing Vdc. It is here noted that the R element of 327 grains is almost independent on Vdc. The results indicate that two phase GBs is a predominant effect on the electrical transport for 327 and exists different transport behavior on Vdc.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering