Domain Walls (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption These nanoscale images of bismuth ferrite thin films show ordered arrays of 71 degree domain walls (top) and 109 degree doman walls (bottom). By changing the polarization direction of the bismuth ferrite, these domain walls give rise to the photovoltaic effect. Credit Image from Seidel, et. al. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.