论文标题
通过集体测量直接估算量子相干性
Direct estimation of quantum coherence by collective measurements
论文作者
论文摘要
最近建立的量子相干性资源理论可以对叠加原理有定量的理解，从量子计算到量子生物学的应用。尽管文献中已经提出了不同的连贯性量化符，但它们在当今实验中的有效估计仍然是一个挑战。在这里，我们介绍了一个集体测量方案，用于估计量子状态中的相干性量，该方案需要在两个国家的两个副本上进行纠缠的测量。正如我们通过数值模拟所示，我们的方案优于基于断层扫描或自适应测量值的其他估计方法，从而在较大的参数范围内具有更高的精度，用于估计Qubit和Qutrit状态的已建立相干量化符。我们表明，通过使用光子实现实验，可以通过实验，在实验和理论之间找到良好的一致性，可以通过当今的技术访问我们的方法。
The recently established resource theory of quantum coherence allows for a quantitative understanding of the superposition principle, with applications reaching from quantum computing to quantum biology. While different quantifiers of coherence have been proposed in the literature, their efficient estimation in today's experiments remains a challenge. Here, we introduce a collective measurement scheme for estimating the amount of coherence in quantum states, which requires entangled measurements on two copies of the state. As we show by numerical simulations, our scheme outperforms other estimation methods based on tomography or adaptive measurements, leading to a higher precision in a large parameter range for estimating established coherence quantifiers of qubit and qutrit states. We show that our method is accessible with today's technology by implementing it experimentally with photons, finding a good agreement between experiment and theory.
