HIGH-ORDER DIFFRACTION AND OPTICAL INFORMATION-STORAGE IN AN AZOBENZENE POLYMER FILM BY MULTIWAVE MIXING

On the basis of photoinduced anisotropy of azobenzene groups, optical information storage with long-term stability in an azobenzene polymer film was performed by multiwave mixing experiments. In two-wave mixing experiments, up to third-order diffraction was observed while up to 4 th-order diffraction was detected in degenerate four-wave mixing exper iments. When the recording beams were removed, the signals (high-order diffraction beams) remained without significant decrease. After the e xperiments, brilliant hologram spot on the film was observed and could be maintained over 180 days without obvious change.