Dielectric measurements have been made on three organosiloxane liquid crystal compounds exhibiting a smectic A (SmA) to smectic C* (SmC*) transition, the SmA phase being of the de Vries type. The electroclinic response of the molecules in the de Vries phase of these compounds exhibits a double-peak profile, and is thus different from the conventional chiral SmA phase, a feature explained on the...

Clock control is one of the mechanisms employed to introduce non-linearity into key stream generators built from linear feedback shift registers. The earliest devices were built from stop-and-go registers while the most recent example, the Shrinking Generator proposed in [2], has an irregular clocking scheme where the number of steps between successive outputs is linked to the length of zero-ru...

We describe a solution for physically obfuscating the representation of a cipher, to augment chips resistance against physical threats, by combining ideas from masking techniques and Physical Obfuscated Keys (POKs). With embedded chips – like RFID tags – as main motivation, we apply this strategy to the representation of a Linear Feedback Shift Register (LFSR). The application of this technique...