Rewritable multicolor fluorescent patterns for multistate memory devices with high data storage capacity

We report a branched polyethyleneimine (BPEI)-quantum dot (QD) based rewritable fluorescent system with a multicolor recording mode, in which BPEI is both QD-multicolor patterning writer and data erasing remover. This method could write distinct colors from size-tailored QDs to represent large numbers of logic states for high data storage capacity.