Estimating expectation values using approximate quantum states
نویسندگان
چکیده
We introduce an approximate description of N-qubit state, which contains sufficient information to estimate the expectation value any observable a precision that is upper bounded by ratio suitably-defined seminorm square root number system's identical preparations xmlns:mml="http://www.w3.org/1998/Math/MathML">M, with no explicit dependence on xmlns:mml="http://www.w3.org/1998/Math/MathML">N. describe operational procedure for constructing state requires, besides quantum preparation, only single-qubit rotations followed measurements. show following this procedure, cardinality resulting grows as xmlns:mml="http://www.w3.org/1998/Math/MathML">3MN. test proposed method Rigetti's processor unit 12, 16 and 25 qubits random states observables, find excellent agreement theory, despite experimental errors.
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ژورنال
عنوان ژورنال: Quantum
سال: 2021
ISSN: ['2521-327X']
DOI: https://doi.org/10.22331/q-2021-03-16-413