Ma Pujuan, Gao Lei, Ginzburg Pavel, Noskov Roman E
1School of Physical Science and Technology of Soochow University, Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, 215006 China.
2Department of Electrical Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv 69978 Israel.
Light Sci Appl. 2018 Oct 17;7:77. doi: 10.1038/s41377-018-0079-9. eCollection 2018.
Bistability is widely exploited to demonstrate all-optical signal processing and light-based computing. The standard paradigm of switching between two steady states corresponding to "0" and "1" bits is based on the rule that a transition occurs when the signal pulse intensity overcomes the bistability threshold, and otherwise, the system remains in the initial state. Here, we break with this concept by revealing the phenomenon of in which the eventual steady state of a resonant bistable system is transformed into a nontrivial function of signal pulse parameters for moderately intense signal pulses. The essential nonlinearity of the indefinite switching allows realization of well-protected cryptographic algorithms with a single bistable element in contrast to software-assisted cryptographic protocols that require thousands of logic gates. As a proof of concept, we demonstrate stream deciphering of the word "enigma" by means of an indefinitely switchable optical nanoantenna. An extremely high bitrate ranging from ~0.1 to 1 terabits per second and a small size make such systems promising as basic elements for all-optical cryptographic architectures.
双稳性被广泛用于演示全光信号处理和基于光的计算。对应于“0”和“1”比特的两个稳态之间切换的标准范式基于这样的规则：当信号脉冲强度超过双稳性阈值时发生转变，否则，系统保持在初始状态。在此，我们打破这一概念，揭示了一种现象，即对于中等强度的信号脉冲，谐振双稳系统的最终稳态转变为信号脉冲参数的非平凡函数。不确定切换的本质非线性使得仅用一个双稳元件就能实现保护良好的加密算法，这与需要数千个逻辑门的软件辅助加密协议形成对比。作为概念验证，我们通过一个可无限切换的光学纳米天线演示了对单词“enigma”的流解密。每秒约0.1至1太比特的极高比特率和小尺寸使此类系统有望成为全光加密架构的基本元件。
