This content has been downloaded from IOPscience. Please scroll down to see the full text. Download details: IP Address: 14.139.193.78 This content was downloaded on 21/11/2013 at 05:39 Please note that terms and conditions apply. Gadolinium substitution induced defect restructuring in multiferroic BiFeO 3 : case study by positron annihilation spectroscopy View the table of contents for this issue, or go to the journal homepage for more 2013 J. Phys. D: Appl. Phys. 46 495309 (http://iopscience.iop.org/0022-3727/46/49/495309) Home Search Collections Journals About Contact us My IOPscience