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arXiv · 1403.2419

Reconfigurable random bit storage using polymer-dispersed liquid crystal

Abstract

We present an optical method of storing random cryptographic keys, at high densities, within an electronically reconfigurable volume of polymer-dispersed liquid crystal (PDLC) film. We demonstrate how temporary application of a voltage above PDLC's saturation threshold can completely randomize (i.e., decorrelate) its optical scattering potential in less than a second. A unique optical setup is built around this resettable PDLC film to non-electronically save many random cryptographic bits, with minimal error, over a period of one day. These random bits, stored at an unprecedented density (10 Gb per cubic millimeter), can then be erased and transformed into a new random key space in less than one second. Cryptographic applications of such a volumetric memory device include use as a crypto-currency wallet and as a source of resettable "fingerprints" for time-sensitive authentication.

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BibTeXRIS

Roarke Horstmeyer, Sid Assawaworrarit, Changhuei Yang. 2014-03-10. Reconfigurable random bit storage using polymer-dispersed liquid crystal. https://arxiv.org/abs/1403.2419

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