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arXiv · 1905.11819

Implementation of generalized measurements on a qudit via quantum walks

Zihao Li·Haoyu Zhang·Huangjun Zhu
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Abstract

Quantum measurements play a fundamental role in quantum mechanics and quantum information processing, but it is not easy to implement generalized measurements, the most powerful measurements allowed by quantum mechanics. Here we propose a simple recipe for implementing generalized measurements on a qudit via quantum walks. With this recipe, any discrete quantum measurement can be implemented via a one-dimensional discrete quantum walk; the number of steps is only two times the number of measurement outcomes. As an illustration, we present a unified solution for implementing arbitrary symmetric informationally complete measurements in dimension 3.

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Zihao Li, Haoyu Zhang, Huangjun Zhu. 2019-05-28. Implementation of generalized measurements on a qudit via quantum walks. https://doi.org/10.1103/physreva.99.062342

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