Minimax Strategy of Optimal Unambiguous State Discrimination

In this paper, we consider the minimax strategy to unambiguously discriminate two pure nonorthogonal quantum states without knowing a priori probability. By exploiting the positive-operator valued measure, we derive the upper bound of the minimax measurement of the optimal unambiguous state discrimination. Based on the linear optical devices, we propose an experimentally feasible scheme to implement a minimax measure of a general pair of two nonorthogonal quantum states.     

静电纺丝法制备纳米纤维及其应用进展

静电纺丝技术是采用物理方法制备一维采用纳米纤维的有效方法,它在大规模制备有序的、复杂的一维纳米材料方面具有很强优势。除了制备一维纤维材料外,电纺丝技术还用于制备二维和三维多孔结构的材料。本文分为三部分,首先介绍了静电纺丝技术的原理和方法;然后综述了静电纺丝技术在制备一维材料方面的研究进展,最后列举了静电纺丝技术在生物工程领域的应用。     

含类Kerr介质的双光子Jaynes-Cummings模型中的反聚束效应

研究了一个两能级原子处于充满了类Ｋｅｒｒ介质的高Ｑ腔里与单模辐射场双光子相互作用的系统中,光场的反聚束效应,着重讨论了原子处于不同初始条件下类Ｋｅｒｒ介质与单模场作用的耦合强度和失谐量对光场反聚束效应的影响。     

Coherence migration in high-dimensional bipartite systems

The conservation law for first-order coherence and mutual correlation of a bipartite qubit state was firstly proposed by Svozilík et al., and their theories laid the foundation for the study of coherence migration under unitary transformations. In this paper, we generalize the framework of first-order coherence and mutual correlation to an arbitrary (m $\otimes$ n)-dimensional bipartite composite state by introducing an extended Bloch decomposition form of the state. We also generalize two kinds of unitary operators in high-dimensional systems, which can bring about coherence migration and help to obtain the maximum or minimum first-order coherence. Meanwhile, the coherence migration in open quantum systems is investigated. We take depolarizing channels as examples and establish that the reduced first-order coherence of the principal system over time is completely transformed into mutual correlation of the (2 $\otimes$ 4)-dimensional system-environment bipartite composite state. It is expected that our results may provide a valuable idea or method for controlling the quantum resource such as coherence and quantum correlations.     

Steering quantum nonlocalities of quantum dot system suffering from decoherence

The important applications of quantum dot system are to implement logic operations and achieve universal quantum computing based on different quantum nonlocalities. Here, we characterize the quantum steering, Bell nonlocality, and nonlocal advantage of quantum coherence (NAQC) of quantum dot system suffering nonunital and unital channels. The results reveal that quantum steering, Bell nonlocality, and NAQC can display the traits of dissipation, enhancement, and freezing. One can achieve the detections of quantum steering, Bell nonlocality, and NAQC of quantum dot system in different situations. Among these quantum nonlocalities, NAQC is the most fragile, and it is most easily influenced by different system parameters. Furthermore, considering quantum dot system coupling with amplitude damping channel and phase damping channel, these quantum nonlocalities degenerate with the enlargement of the channel parameters $t$ and $\varGamma$. Remarkably, measurement reversal can effectively control and enhance quantum steering, Bell nonlocality, and NAQC of quantum dot system suffering from decoherence, especially in the scenarios of the amplitude damping channel and strong operation strength.     

实现最优普适1到2实数态量子克隆的方案

提出了基于腔QED的一种实验上可行的方案去实现最优普适1→2 实数态量子克隆机制。在这个的方案中,三个原子中的两个同时与腔场发生作用,并且它们受经典场的作用。基于当前的腔QED技术,此方案是可以实现的。     

用W态实现量子隐形传态的腔QED方案

本文提出一个用类W态作为纠缠通道,采用不同于文献[19]的测量基来实现量子隐形传态的腔QED方案.在这个方案里,只需要利用原子和腔场通过J-C哈密顿量发生共振相互作用,一步就可制备纠缠通道.另外,通过原子与腔场的失谐作用,利用Bell态测量,可实现概率为100%的量子隐形传态.在目前的腔QED技术条件下,该方案是可以实现的.     

Linear Optical Scheme for Implementing Optimal Real State Cloning

We propose an experimental scheme for implementing the optimal 1 → 3 real state cloning via linear optical elements. This method relies on one polarized qubit and two location qubits and is feasible with current experimental technology.