| （英） |
Recently a number of efficient methods for quantum state estimation have been proposed, demanding methods for accurate state estimation for systems with large sizes. Variational approaches introduce simplifying assumptions on the form of the quantum state, allowing the estimation with a small number of measurement data. Most of the approaches prepare parametric models for the quantum state and perform parameter estimation based on measurement data. In particular, it is known that using the well-established statistical method called the "information criterion", it is possible to reduce the excess errors (induced by the simplifying assumptions) by using a small number of parameters. In this study, we propose a new "quantum information criterion", which is independent of a measurement strategy we take. Using this quantity, the estimated model is evaluated based on the quantum relative entropy. Using the Quantum Hamiltonian-Based Model, a quantum state model that describes mixed states, we will investigate the performance of this method through numerical experiments. |