Distributed quantum computation over noisy channels
Distributed quantum computation over noisy channels
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DOI：
10.1103/physreva.59.4249
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发表时间：
1999-06-01
影响因子：
2.9
通讯作者：
Macchiavello, C
中科院分区：
文献类型：
--
作者：
Cirac, JI;Ekert, AK;Macchiavello, C
我们分析了利用纠缠态在量子网络中的远距离节点之间进行非局域量子计算。与多粒子纠缠态的产生相关的复杂性是量化的全局成本的概念。此参数允许我们比较不同方案中物理资源的使用情况。我们表明，对于理想的通道和足够大的节点数，使用最大纠缠态是有利的不相关的。对于有噪声的信道，必须使用纠缠纯化程序，以创建高保真度的纠缠态。我们证明了，在某些情况下，提供最大纠缠输入的量子网络仍然会产生较小的全局代价，前提是a属于给定的区间a是[n（min），n（max）]的元素。的n（最小值）和n（最大值）的值至关重要地取决于用于建立I？处理器纠缠态，以及在计算过程中的退相干过程的存在。相位估计问题已被用来说明这一事实。[S1050-2947（99）09606-7]。
We analyze the use of entangled states to perform quantum computations nonlocally among distant nodes in a quantum network. The complexity associated with the generation of multiparticle entangled states is quantified in terms of the concept of global cost. This parameter allows us to compare the use of physical resources in different schemes. We show that, for ideal channels and for a sufficiently large number of nodes, the use of maximally entangled states is advantageous over uncorrelated ones. For noisy channels, one has to use en tanglement purification procedures in order to create entangled states of high fidelity. We show that under certain circumstances a quantum network supplied with a maximally entangled input still yields a smaller global cost, provided that a belongs to a given interval a is an element of [n(min) ,n(max)]. The values of n(min) and n(max) crucially depend on the purification protocols used to establish the I? processor entangled states, as well as on the presence of decoherence processes during the computation. The phase estimation problem has been used to illustrate this fact. [S1050-2947(99)09606-7].