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Russian Microelectronics

Development of Fuzzy Quantum Measurement Protocols for Ionic Qudits

K. B. Koksharov, Bogdanov Yu, B. I. Bantysh, V. F. Lukichev

Published Dec 1, 2025• 0 citations
Publisher

Abstract

Abstract A model for calculating quantum tomography protocols of ionic qudits is proposed, which allows taking into account errors in setting transformation parameters during measurements. The fidelity of ionic qudit tomography under errors in specifying transformation parameters is compared between the standard method and the method of fuzzy quantum measurements. A radical advantage of the fuzzy quantum measurement model over the standard model is demonstrated. It is shown that the developed model makes it possible to obtain a set of two-level of quantum state transformations of qudits that ensures the implementation of the given quantum measurement protocol.

DOI
10.1134/s106373972560092x

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Abstract A model for calculating quantum tomography protocols of ionic qudits is proposed, which allows taking into account errors in setting transformation parameters during measurements. The fidelity of ionic qudit tomography under errors in specifying transformation parameters is compared between the standard method and the method of fuzzy quantum measurements. A radical advantage of the fuzzy quantum measurement model over the standard model is demonstrated. It is shown that the developed model makes it possible to obtain a set of two-level of quantum state transformations of qudits that ensures the implementation of the given quantum measurement protocol.
We propose a model for quantum tomography protocols of ion-trap qudits that incorporates parameter-setting errors in measurement transformations. A comparative analysis of reconstruction accuracy under transformation uncertainty is conducted for both the conventional projective measurement approach and the fuzzy quantum measurement framework. The results demonstrate a substantial advantage of the fuzzy measurement model in the presence of transformation inaccuracies. Furthermore, the model enables the construction of a complete set of two-level unitary transformations applicable to qudit states.
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Multilevel quantum states (qudits) represent a promising platform for scalable quantum comput-ing. In this paper, we present a method for precisely controlling such systems using fuzzy quantum measure-ments. The developed method is used for a precise reconstruction of quantum states under conditions of a significant effect of decoherence and quantum noise. Protocols for quantum measurements based on mutu-ally unbiased bases (MUBs) of various dimensions are considered. The accuracy characteristics of sets of ran-dom states uniformly distributed with respect to the Haar measure are studied.