Department of Physics, Stanford University, Stanford, California 94305, USA.
Department of Applied Physics, Stanford University, Stanford, California 94305, USA.
Phys Rev Lett. 2013 Nov 27;111(22):223602. doi: 10.1103/PhysRevLett.111.223602.
We consider a general class of integrated quantum systems where photon-photon interaction occurs in a quantum device that is localized in space. Using techniques that are closely related to cluster decomposition principles in quantum field theory, we provide a general constraint on the analytic properties of a two-photon S matrix in this class of systems. We also show that the photon-photon interaction in these systems inevitably leads to frequency mixing and entanglement and that frequencies of the single photons cannot be preserved in these systems.
我们考虑一类广义的集成量子系统，其中光子-光子相互作用发生在空间局域的量子器件中。利用与量子场论中的集团分解原理密切相关的技术，我们对这一类系统中双光子 S 矩阵的解析性质给出了一个普遍约束。我们还表明，这些系统中的光子-光子相互作用不可避免地导致频率混合和纠缠，并且这些系统中不能保持单光子的频率。
