Surface plasmons (SPs) propagating along the interface between metals and dielectrics are capable of tailoring light matter interaction at the nanoscale, which emerges as a research frontier in nanophotonics. In this talk, we introduce the recent progress of high capacity optical information technologies through multi-dimensional optical multiplexing mediated by plasmonic nanostructures and nanocomposites. Through the investigation of plasmonic resonance in metallic nanorods and the subsequent photothermal reshaping mechanism, information can be multiplexed and encoded in the physical dimensions of light. It enables optical recording with orders of magnitude increased capacity as well as security. In addition, we show plasmonic nanostructures capable of light field manipulation in multi-dimensions. Therefore, light field carrying multiple information can be reconstructed with great flexibility and controllability.