Green-Light Static Rewritable Optical Storage Properties of a Novel CuTCNQ Derivative Thin Film

A novel charge-transfer complex film: copper-(n-propyl ester 7,7,8,8- tetracyanoquinodimethane-2,5-ylene-(3-propionic acid)) (Cu-TCNQ(C₂H₄COOC₃H₇)₂) was prepared by spin-coating. Absorption spectra, green-light (514.5 nm) static rewritable optical recording properties and rewritable mechanism of this film were studied. The results show that there are two strong absorption peaks at 388 nm and 675 nm, which can be assigned to electronic transitions in anion radical TCNQ(C₂H₄COOC₃H₇)^-₂. Green-light optical storage experimental results of this film were as follows: write-in power was 9 mW, pulse duration was 80 ns; erasing power was 4 mW, pulse duration was 500 ns; the reflectivity contrast C ≥15%; number of write-erase cycle N ≥ 100. It is found that the realization of rewritable optical storage of the Cu-TCNQ (C₂H₄COOC₃H₇)₂ film is related to the reversible changes of the optical properties, which is caused by the reversible charge transfer between copper and n-propyl ester 7,7,8,8- tetracyanoquinodimethane-2,5-ylene-(3-propionic acid) in the complex through inducement of laser irradiation.