We sketch a relation between two crucial, yet independent, fields in quantum information research, viz. quantum decoherence and quantum cryptography. We investigate here how the standard cryptographic assumption of shielded laboratory, stating that data generated by a secure quantum device remain private unless explicitly published, is disturbed by the einselection mechanism of quantum Darwinism explaining the measurement process by interaction with the external environment. We illustrate the idea with a paradigmatic example of a quantum random number generator compromised by an analog of the Van Eck phreaking. In particular, we derive a trade-off relation between eavesdropper's guessing probability $P_{guess}$ and the collective decoherence factor $\Gamma$ of the simple form $P_{guess} + \Gamma \geq 1$.
翻译:我们绘制了量子信息研究中两个重要而又独立的领域之间的关系,即量子脱节和量子加密。我们在这里调查了屏蔽实验室的标准加密假设,指出安全量子装置产生的数据除非明确公布,否则仍属私人性质,我们受到量子达尔文主义的不选机制的干扰,该机制通过与外部环境的互动解释测量过程。我们用一个典型的例子来说明这个想法,即量子随机数字生成器因范埃克的模拟而受损。特别是,我们得出了窃听器的猜测概率$P ⁇ gues}$和简单形式的集体脱节系数$\Gamma$+\Gamma =Ge1$之间的权衡关系。