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arXiv · 2108.03448

Quantum State Tomography as a Bilevel Problem, Utilizing I-Q Plane Data

Georgios Korpas·Jakub Marecek
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Abstract

It is natural to ask how to utilize actual measurements, such as the so-called IQ-plane data obtained in the dispersive readout of transmon qubits, in the estimation of the state of a quantum system. We formulate the joint problem of discrimination and quantum state tomography as a bilevel optimization problem and show how to solve it. The use of the joint problem can improve the sample complexity (or the reconstruction error for a fixed number of measurements) compared with traditional techniques that decompose the problem into the discrimination and state tomography based on the estimated expectation values of certain projective measurement operators.

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Georgios Korpas, Jakub Marecek. 2021-08-07. Quantum State Tomography as a Bilevel Problem, Utilizing I-Q Plane Data. https://arxiv.org/abs/2108.03448

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