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arXiv · 2205.10108

An uncertainty relation for measurements of random unitary channels acting on a qubit

Taihei Kimoto·Takayuki Miyadera
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Abstract

By preparing an input state and measuring an observable for the output state, we can measure a quantum channel. Following the formulation given by Xiao et al., we study an uncertainty relation for ancilla-free measurements of random unitary channels acting on a qubit. We obtain an explicit formula and give a necessary and sufficient condition for this formula to be nontrivial.

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Taihei Kimoto, Takayuki Miyadera. 2022-05-20. An uncertainty relation for measurements of random unitary channels acting on a qubit. https://doi.org/10.7566/jpsj.92.034005

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