generalized joint higher-rank numerical range
Abstract
the rank-k numerical range has a close connection to the construction of quantum error correction code for a noisy quantum channel. for noisy quantum channel, a quantum error correcting code of dimension k exists if and only if the associated joint rank-k numerical range is non-empty. in this paper the notion of joint rank-k numerical range is generalized and some statements of [2011, generalized numerical ranges and quantum error correction, j. operator theory, 66: 2, 335-351.] are extended.