Three-dimensional erasable optical memory using a photochromic diarylethene single crystal as the recording medium

Abstract

Three-dimensional erasable optical recording in a single crystal of 1, 2-bis(3-methyl-2-thienyl)perfluorocyclopentene (1), which shows a reversible fluorescence change with the photochromic reaction, has been demonstrated. The recorded spot size read by a fluorescence-detection method was approximately 200nm in plane and 1.5μm in depth, which corresponds to the recording density higher than 5Tbit/cm3. The recorded spots were erased by irradiation with visible light. The writing/reading/erasing cycle could be repeated more than 104 times.