Optical diarylethenes

Corredor CC, Huang Z, Belfield KD (2006) Two-photon 3D optical data storage via fluorescence modulation of an efficient fluorene dye by a photochromic diarylethene. Adv Mater 18 2910-2914... 

Irie et al. reported on the absolute reversible photocyclization reactions of achiral diarylethene 52 in chiral crystal leading to 53 in up to 99% ee. The asymmetric photochromic material has potential application in nonlinear optics, for example, in switchable second harmonic generation devices. [32]... 

Fig. 11 shows the photoswitching of the injection current. Upon UV irradiation, the hole injection current increased, while decreasing to zero on irradiation with visible light. Very thin amorphous diarylethene film as thin as 0.2 pm could also control the hole injection to the organic hole transport layer (Fig. 9b). These results are potentially applicable to optical memory-type organic photoconductors.

Optically active bis-imine-functionalized diarylethene (2-4 %) (Scheme 13) was used as a chiral, photoresponsive dopant in the nematic LC materials K15 and ZLI-389, resulting in stable cholesteric phases. For the open form of 26a, [5m values of 11 [tm-1 (K15) and 13 xm 1 (ZLI-389) were measured, while the closed form 26b did not show any helical twisting power. Irradiation at 300 nm (30-50 s) resulted in the closed form and disappearance of the cholesteric phase. Irradiation with visible light restored the cholesteric phase. The gradual decrease in pitch, representing a multi-... 

S. L. Gilat, S. H. Kawai, and J.-M. Lehn, Light-triggered molecular devices photochemical switching of optical and electrochemical properties in molecular wire-type diarylethene species, Chem. Eur. J1, 275-284 (1995). 

M. Irie, Photochromic diarylethenes for optical data storage media, Mol. Cryst. Liq. 227, 263-270 (1993). 

As in previous years, thiophene based diarylethene derivatives constitute an important class of materials which are considered as promising candidates for various kinds of optoelectronic devices, such as switches and optical memories. 

Fukaminato, T., Kobatake, S., Kawai, T, and Irie, M. Three-dimensional erasable optical memory using a photochromic diarylethene single cry stal as the recording medium. Proc. Jpn. Acad. 77, B, 30, 2001. 

Hoshino, M., Ebisawa, F., Yoshida, T., and Sukegawa, K. Refractive index change in photochromic diarylethene derivatives and its application to optical switching devices. J. Photochem. Photobiol. A Chem. 1997, 105, 75. 

Fulgides and related diarylethenes have been investigated extensively because of the long-term thermal stability of their photocyclized colored forms, which could lead to this application in erasable optical recording materials and photoswitchable optical elements. The entrapment of these photochromic molecules in polymer films is necessary for these practical applications. Picosecond laser photolysis was employed to study the electrocyclic reaction of a furylfulgide (18, Figure 8) in polymer solids and revealed that the colored structure was formed with a time constant of ca. lOps irrespective of the nature of the polymer matrix.49... 

Case Study 6.4 Optical information storage - photochromic diarylethenes... 

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