研究了耦合到由 Su-Schrieffer-Heeger（SSH）型耦合腔阵列构成的光子波导的两个二能级巨型原子的纠缠产生。这里，每个原子通过两个耦合点与波导耦合。研究了两原子分离耦合情形，并针对两个原子与波导之间耦合点的分布考虑了16种耦合构型。推导了量子主方程来支配两个原子的演化，并通过计算两原子态的 concurrence（共生纠缠度）来表征原子纠缠。研究发现，两个巨型原子的纠缠依赖于耦合构型以及巨型原子的耦合点距离。特别地，在14种耦合构型中，两个巨型原子的纠缠动力学依赖于 SSH 波导的二聚化参数。根据两个巨型原子的自能，发现这16种耦合构型中有10种可以划分为五对。结果还表明，在这五对耦合构型中，两个巨型原子之间纠缠的延迟突然出现在很大程度上得到增强。本工作将促进巨型原子拓扑波导 QED 系统中量子效应与相干操控的研究。
英文摘要：
The entanglement generation of two two-level giant atoms coupled to a photonic waveguide, which is formed by a Su-Schrieffer-Heeger (SSH) type coupled-cavity array is studied. Here, each atom is coupled to the waveguide through two coupling points. The two-atom separate-coupling case is studied, and 16 coupling configurations are considered for the coupling-point distributions between the two atoms and the waveguide. Quantum master equations are derived to govern the evolution of the two atoms and characterize atomic entanglement by calculating the concurrence of the two-atom states. It is found that the two giant-atom entanglement depends on the coupling configurations and the coupling-point distance of the giant atoms. In particular, the entanglement dynamics of the two giant atoms in 14 coupling configurations depend on the dimerization parameter of the SSH waveguide. According to the self-energies of the two giant atoms, it is found that ten of these 16 coupling configurations can be divided into five pairs. It is also showed that the delayed sudden birth of entanglement between the two giant atoms is largely enhanced in these five pairs of coupling configurations. This work will promote the study of quantum effects and coherent manipulation in giant-atom topological-waveguide-QED systems.
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