量子Zeno效应与JC系统中的纠缠

Quantum Zeno Effects and the Entanglement of JC Model

摘要: 对原子-场相互作用系统，在Jaynes-Cummings (JC)模型下，研究了频繁测量与原子-场间纠缠度的关系。数值计算结果表明，失谐度越大测量后初态存活几率的衰减率与原子-场的纠缠度均越小；随着测量的时间间隔的减小，初态存活几率趋向不衰减，出现了量子Zeno效应。结果得出，频繁测量和减小失谐度可以抑制初态存活几率的衰减。原子-场纠缠度与初态存活几率存在一定的联系，即改变失谐度的大小使原子-场纠缠度与初态存活几率的变化趋势一样。

Abstract: In the field-atom interaction system, the relation between the frequently-repeated measurement and the entanglement of the field-atom is investigated within Jaynes-Cummings (JC) model. Nu-merical calculations indicate that the entanglement of the field-atom and survival probability monotonously decrease with the increase of detuning degree. However, the trend of survival probability maintains little attenuation with the reduction of time-intervals, and this could be re-garded as the generation of quantum Zeno effect. We eventually draw a conclusion that the decay of survival probability could be efficiently suppressed through the increase of the measurement frequency and reduction of detuning. Moreover, there exist some relationships between the entanglement of the field-atom and survival probability. The changing detuning makes the entanglement of the field-atom and survival probability have the same variation tendency.