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Journal of Physics A Mathematical and Theoretical

An elementary constructive approach to the higher-rank numerical ranges of unitary matrices and quantum error-correcting codes

Alexander Ya. Kazakov

Published May 23, 2008• 1 citation
Publisher

Abstract

One of the main ingredients of the quantum error-correcting codes theory is the study of the higher-rank numerical ranges of the operators related to the error operators. We constructively verify a conjecture on the structure of higher-rank numerical ranges for unitary matrices.
DOI
10.1088/1751-8113/41/25/255306

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