Hybrid carbon nanotube and dye-doped liquid crystal material for holographic imaging

Without the application of AC or DC electric fields, we recorded permanent holographic images in a hybrid material based on the nematic liquid crystal E7, doped with 0.6% Methyl Red (MR) and 0.002% single-wall carbon nanotubes (CNTs). The images were recorded using a 488-nm laser and reconstructed using 488, 532 and 633-nm probe beams. Multi-order diffraction patterns were observed, during image storage and reconstruction, for thin films having thicknesses of 15 μm. The quality and diffraction efficiency were higher for the hybrid cells than for cells doped only with MR. Average first-order diffraction efficiencies of 7.1 and 3.7% were found for the hybrid and MR-only doped cells, respectively. The primary objective of this study was to utilize the molecular properties of MR and CNTs to produce a hybrid material with improved holographic properties. Dynamics of image formation and a proposed CNT-enhancement mechanism are presented. The holograms are robust and have remained stable for over 2 years.