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arXiv · 1610.03714

Quantum state estimation when qubits are lost: A no-data-left-behind approach

Brian P. Williams·Pavel Lougovski
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Abstract

We present an approach to Bayesian mean estimation of quantum states using hyperspherical parametrization and an experiment-specific likelihood which allows utilization of all available data, even when qubits are lost. With this method, we report the first closed-form Bayesian mean estimate for the ideal single qubit. Due to computational constraints, we utilize numerical sampling to determine the Bayesian mean estimate for a photonic two-qubit experiment in which our novel analysis reduces burdens associated with experimental asymmetries and inefficiencies. This method can be applied to quantum states of any dimension and experimental complexity.

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Brian P. Williams, Pavel Lougovski. 2016-11-03. Quantum state estimation when qubits are lost: A no-data-left-behind approach. https://doi.org/10.1088/1367-2630%2Faa65de

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