We address the performance of a coin-biased quantum walk as a generator for non-classical position states of the walker. We exploit a phenomenon of coherent localization in the position space - resulting from the choice of small values of the coin parameter and assisted by post-selection - to engineer large-size coherent superpositions of position states of the walker. The protocol that we design appears to be remarkably robust against both the actual value taken by the coin parameter and strong dephasing-like noise acting on the spatial degree of freedom. We finally illustrate a possible linear-optics implementation of our proposal, suitable for both bulk and integrated-optics platforms.

中文翻译：

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通过偏置硬币量子行走中的相干局域化实现鲁棒的量子态工程。

我们研究了硬币偏置量子行走作为行走者非经典位置状态生成器的性能。我们利用位置空间中的相干定位现象（由于选择硬币参数的小值并在后选择的帮助下产生）来设计步行者位置状态的大尺寸相干叠加。我们设计的协议似乎对于硬币参数所取的实际值和作用于空间自由度的强相移噪声都非常稳健。最后，我们说明了我们建议的可能的线性光学实现，适用于散装和集成光学平台。