Paper Memory writes it down to remember, using new techniques to create paper flash drives:

Martins, a scientist at the New University of Lisbon in Portugal, continues: “What we have shown is that it is possible to store information on paper, electronically, for more than a year and a half.”

“What we are doing is exploiting the memory effect,” Martins explains. “We have a sort of type of integrated foam composed of fibers set up that increases the capability of storing carriers – or charges – in our paper.” These charges allow the paper to display information that is also erasable – and the paper is rewritable so that additional information can be added.

To create the paper, long fibers from pine and polyester were mixed together and put into an ionic resin matrix. The fibers were then coated with gallium indium zinc oxide, using magnetron sputtering. “We have integrated discrete fibers, and contacts are applied on the extremes of the channel region to allow the induced carriers to move,” Martins says. “Electrons move along the fibers.”

Martins points out that another of the attractive features of this paper is its ability to hold multiple layers of information. “If I want my paper to catch information,” he explains, “I can apply a signal of, say, five volts. And it writes on the paper. If I want to erase the information, I basically apply minus five volts – the opposite. But, at the same time, I can write another layer of information using 10 volts. The paper can distinguish between the two, and even if I erase the five volt information, the 10 volt information remains.”