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arXiv · 2308.14262

Experimental simulation of quantum superchannels

Hang Li·Kai Wang·Shijie Wei·Fan Yang·Xinyu Chen·Barry C. Sanders·Dong-Sheng Wang·Gui-Lu Long
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Abstract

Simulating quantum physical processes has been one of the major motivations for quantum information science. Quantum channels, which are completely positive and trace preserving processes, are the standard mathematical language to describe quantum evolution, while in recent years quantum superchannels have emerged as the substantial extension. Superchannels capture effects of quantum memory and non-Markovianality more precisely, and have found broad applications in universal models, algorithm, metrology, discrimination tasks, as examples. Here, we report an experimental simulation of qubit superchannels in a nuclear magnetic resonance (NMR) system with high accuracy, based on a recently developed quantum algorithm for superchannel simulation. Our algorithm applies to arbitrary target superchannels, and our experiment shows the high quality of NMR simulators for near-term usage. Our approach can also be adapted to other experimental systems and demonstrates prospects for more applications of superchannels.

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Hang Li, Kai Wang, Shijie Wei, Fan Yang, Xinyu Chen, Barry C. Sanders, Dong-Sheng Wang, Gui-Lu Long. 2023-08-28. Experimental simulation of quantum superchannels. https://doi.org/10.1088/1367-2630%2Fad1c91

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