论文标题
观察$ \ Mathcal {pt} $ - 单个离子系统中的对称量子连贯性
Observation of $\mathcal{PT}$-symmetric quantum coherence in a single ion system
论文作者
论文摘要
平均时间（$ \ Mathcal {pt} $） - 对称系统，尽管具有非富特性，但具有真正的特征值，但已被广泛用于实现古典领域中的异国功能，例如损失诱导的透明度或激烈的复兴。通过接近特殊点（EP）或特征态的融合，也有望在纯量子$ \ Mathcal {pt} $设备中出现非常规的效果。在这里，我们报告了自发$ \ Mathcal {pt} $对称性的实验证据，以单个冷$^{40} \ Mathrm {Ca}^{+} $ ion，更重要的是，更重要的是，EP在EP中出现的完美量子相关性的反直觉效果。确定了实验结果与理论预测之间的良好一致性。鉴于冷离子在构建量子内存或处理器中的多功能作用，我们的实验为探索和利用纯量子EP效应提供了一个新的平台，并在捕获离子的量子工程中采用了不同的应用。
Parity-time($\mathcal{PT}$)-symmetric systems, featuring real eigenvalues despite its non-Hermitian nature, have been widely utilized to achieve exotic functionalities in the classical realm, such as loss-induced transparency or lasing revival. By approaching the exceptional point (EP) or the coalescences of both eigenvalues and eigenstates, unconventional effects are also expected to emerge in pure quantum $\mathcal{PT}$ devices. Here, we report experimental evidences of spontaneous $\mathcal{PT}$ symmetry breaking in a single cold $^{40}\mathrm{Ca}^{+}$ ion, and more importantly, a counterintuitive effect of perfect quantum coherence occurring at the EP. Excellent agreement between experimental results and theoretical predictions is identified. In view of the versatile role of cold ions in building quantum memory or processor, our experiment provides a new platform to explore and utilize pure quantum EP effects, with diverse applications in quantum engineering of trapped ions.
