OPTICAL MEMORY EFFECT IN GAN EPITAXIAL-FILMS

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