Photoinduced polarization gratings in molecular glass containing azobenzene and chiral isosorbide moieties

In this work, high efficient polarization gratings have been optically recorded in a molecular glass composed of both azobenzene and chiral isosorbide moieties. In the process, the molecular glass films were sandwiched between two-pieces of glass slides and irradiated with interfering Ar+ laser beams. The grating fabrication was tested by using both the two circularly polarized beams with orthogonal polarization (RCP + LCP) and two linearly polarized beams (p + p). The polarization gratings were observed by polarization optical microscopy and characterized by polarization analyses of the diffracted beams. Results show that the gratings produced are coincident with the period modulation of the light field. The polarization modulation by two circularly polarized Ar+ beams can induce the grating formation in a much more efficient way. The diffraction efficiency of the gratings can reach 13.4% after 5 s irradiation with the circularly polarized Ar+ laser beams (59 mW/cm2 for each beam). The gratings are stable for at least three months when stored at room temperature. The gratings can be erased by irradiation of a circularly polarized Ar+ laser single beam. The writing and erasing cycle can be repeated many times without lose of the recording efficiency. The molecular glass reported in this work could be used as a new material for holographic data-storage and others.