Optical memory effect in GaN epitaxial films

We report on memory effects in the optical properties of GaN and AIN epitaxial-films grown by atmospheric pressure metal organic chemical vapor deposition. After exposing selected areas of particular samples with He-Cd laser light (3.8 eV), we observed a persistent and marked decrease in the near band edge photoluminescence (PL) intensity emitted from these areas. This effect has been observed in epitaxial films that typically have a pyramidlike hillock surface. This ability to modulate PL emission intensity at individual points in these materials can be exploited as a method for optical data storage. A means of erasing information stored using this effect has also been investigated using lower energy (similar to 2 eV). (C) 1997 American Institute of Physics.