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arXiv quant-ph/0602164quant-ph
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程序简单的可编程量子态鉴别器

Programmable quantum state discriminators with simple programs

Janos A. Bergou, Vladimir Buzek, Edgar Feldman, Ulrike Herzog, Mark Hillery

摘要:

我们描述了一类可以区分两个量子态的可编程器件。我们考虑两种情况。在第一种情况下,这两种状态都是未知的。每个未知状态的一个副本被提供作为两个程序寄存器的输入或程序,并且保证在一个程序状态中准备的数据状态被馈送到设备的数据寄存器中。然后,该设备将以最佳方式告诉我们,存储在程序寄存器中的哪个模板与数据状态匹配。在第二种情况下,我们知道其中一个状态,而另一个状态未知。未知状态的一个副本被馈送到单个程序寄存器中,并且保证在程序状态或已知状态中准备的数据状态被馈送到数据寄存器中。然后,设备将再次以最佳方式告诉我们数据状态是否与模板匹配或是否为已知状态。我们确定两种类型的最佳设备。第一个执行最小误差的歧视,第二个执行最佳的明确的歧视。在所有情况下,我们首先处理数据状态只有一个副本的简单问题,然后将处理推广到n个副本。与其他工作相比,我们发现,提供n > 1个副本的数据状态产生更高的成功概率比提供n > 1个副本的程序状态。

英文摘要:

We describe a class of programmable devices that can discriminate between two quantum states. We consider two cases. In the first, both states are unknown. One copy of each of the unknown states is provided as input, or program, for the two program registers, and the data state, which is guaranteed to be prepared in one of the program states, is fed into the data register of the device. This device will then tell us, in an optimal way, which of the templates stored in the program registers the data state matches. In the second case, we know one of the states while the other is unknown. One copy of the unknown state is fed into the single program register, and the data state which is guaranteed to be prepared in either the program state or the known state, is fed into the data register. The device will then tell us, again optimally, whether the data state matches the template or is the known state. We determine two types of optimal devices. The first performs discrimination with minimum error, the second performs optimal unambiguous discrimination. In all cases we first treat the simpler problem of only one copy of the data state and then generalize the treatment to n copies. In comparison to other works we find that providing n > 1 copies of the data state yields higher success probabilities than providing n > 1 copies of the program states.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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