Zeno and anti-Zeno effect in an open quantum system in the ultrastrong-coupling regime
Zeno and anti-Zeno effect in an open quantum system in the ultrastrong-coupling regime
复制标题
超强耦合态开放量子系统中的芝诺效应和反芝诺效应
DOI：
10.1103/physreva.95.062109
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发表时间：
2017-06-09
影响因子：
2.9
通讯作者：
Zheng, Hang
中科院分区：
文献类型：
--
作者：
He, Shu;Chen, Qing-Hu;Zheng, Hang
研究了与谐振子相互作用的二能级系统的量子Zeno效应(QZE)和量子反Zeno效应(QAZE)。通过应用基于矩阵乘积态的数值精确方法，必须对以前得到的反旋转项影响的图像进行修正：对于物理浴初始态，随着测量间隔的增加，只在弱耦合时没有从QZE到QAZE的转变，而在强耦合时存在。此外，我们还发现，对于广泛使用的裸浴初始态，这种转变总是发生的。在只投影测量量子比特的更现实的测量方案中，除了中间测量间隔的加速衰变之外，对于裸浴初始态的上述场景在性质上保持不变。
We study the quantum Zeno effect (QZE) and quantum anti-Zeno effect (QAZE) of a two-level system interacting with an environment of harmonic oscillators, the spin-boson model. By applying a numerically exact method based on matrix product states, the previously obtained picture on the influence of counter-rotating terms has to be modified: For physical bath initial states, the transition from QZE to QAZE with increasing measurement interval is only absent at weak coupling, while present at strong coupling. Furthermore, we find that the transition occurs always for the widely used bare bath initial state. Within a more realistic measurement scheme where only the qubit is projectively measured, the above scenario for the bare bath initial state remains qualitatively unchanged, apart from accelerated decay for intermediate measurement intervals.