H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom.
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain.
Phys Rev Lett. 2018 Jun 29;120(26):260401. doi: 10.1103/PhysRevLett.120.260401.
We consider the generation of randomness based upon the observed violation of an Einstein-Podolsky-Rosen (EPR) steering inequality, known as one-sided device-independent randomness generation. We show that in the simplest scenario-involving only two parties and two measurements for the uncharacterised party with d outcomes-that there exist EPR steering inequalities whose maximal violation certifies maximal randomness generation, equal to log(d) bits. We further show that all pure partially entangled full-Schmidt-rank states in all dimensions can achieve maximal violation of these inequalities, and thus lead to maximal randomness generation in the one-sided device-independent setting. More generally, the amount of randomness that can be generated is given by a semidefinite program, which we use to study the behavior for nonmaximal violations of the inequalities.
我们考虑基于观察到的爱因斯坦-波多尔斯基-罗森(Einstein-Podolsky-Rosen,EPR)导引不等式的违反来生成随机性,这种方法被称为单边无设备的随机性生成。我们表明,在最简单的情况下——仅涉及两个参与者和一个未被描述的参与者的两个测量,该参与者具有 d 个结果——存在 EPR 导引不等式,其最大违反程度证明了最大的随机性生成,等于 log(d) 比特。我们进一步表明,所有维度的纯部分纠缠全施密特秩态都可以实现这些不等式的最大违反,从而在单边无设备的情况下导致最大的随机性生成。更一般地,通过半定规划可以得到可生成的随机性的数量,我们使用它来研究不等式的非最大违反情况下的行为。