RET-based two-photon photochromic optical data storage

ORGN 457

Claudia C. Corredor, ccorredo@mail.ucf.edu1, Zhen-Li Huang, huangz@creol.ucf.edu2, Kevin D. Belfield, belfield@mail.ucf.edu2, Alma R. Morales, amorales@mail.ucf.edu1, and Mykhailo V. Bondar, mike_bondar@hotmail.com3. (1) Department of Chemistry, University of Central Florida, 4000 Central Florida Blvd., P.O. Box 162366, Orlando, FL 32816-2366, (2) Department of Chemistry and CREOL, College of Optics and Photonics, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816-2366, (3) Department of Photoactivity, Institute of Physics, National Academy of Sciences of Ukraine, Prospect Nauki 46, Kiev, Ukraine
The modulation of the emission intensity of several fluorene derivatives such as poly(9,9-didecyl-2,7-dipheylaminofluorene) (2) (donor) by the closed form of diarylethene 1 (acceptor) was studied. Föster distances and critical concentrations were calculated from the spectral overlap of the donor's emission (fluorene derivatives) and the acceptor's absorption (closed form of diarylethene 1) in solution and in polymer films of PMMA-co-VBP. Calculated values strongly suggest that a Förster- type RET mechanism is involved in this fluorescence modulation. A bichromophoric RET-based two-photon photochromic optical data storage system is also presented. The recording mechanism in this system is based on two-photon excitation of the closed form of diarylethene 1 at 800 nm. Readout by two-photon excitation at 800 nm was performed 10,000 times without significantly compromising the stored data. Differences in the non-linear absorption behavior of the two components in this system allowed recording and read-out using the same excitation wavelength but different laser intensities.