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arXiv · 2103.10219

Experimental SWAP test of infinite dimensional quantum states

Chi-Huan Nguyen·Ko-Wei Tseng·Gleb Maslennikov·H. C. J. Gan·Dzmitry Matsukevich
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Abstract

Efficient overlap estimation of high-dimensional quantum states is an important task in quantum information and a core element in computational speedups of quantum machine learning. Here we experimentally demonstrate the SWAP test that measures the overlap of two motional states in a system of trapped $^{171}\mathrm{Yb}^+$ ions. To illustrate the versatility of our implementation, we report the overlap measurement of a variety of quantum states: Fock states, coherent states, squeezed vacuum states, and cat states. We highlight applications of the SWAP test by measuring the purity of mixed states. Our results enable quantum information processing with high dimensional quantum states.

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Chi-Huan Nguyen, Ko-Wei Tseng, Gleb Maslennikov, H. C. J. Gan, Dzmitry Matsukevich. 2021-03-18. Experimental SWAP test of infinite dimensional quantum states. https://arxiv.org/abs/2103.10219

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