Spatial Projection of Electronic Conductivity: The Example of Conducting Bridge Memory Materials

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Conducting bridge random access memory materials have special promise for FLASH memory, other applications beside, and also special potential for continued miniaturization. They are electronic materials of unique flexibility. Here, we offer new models of Cu-doped alumina, and reveal qualitative differences in the behavior of transition metal ions in chalcogenide and oxide hosts, showing that Cu clusters in an amorphous alumina host, in contrast with chalcogenides in which the metal atoms do not cluster. We further elucidate the processes of electron transport. To determine these, the Kubo–Greenwood formula is cast in a form to enable the estimate of a space-projected conductivity. The method reveals those parts of the networks that may conduct a current (or absorb radiation at frequency ω)