English

Nuclear Numerical Range and Quantum Error Correction Codes for non-unitary noise models

Quantum Physics 2017-01-31 v1

Abstract

We introduce a notion of nuclear numerical range defined as the set of expectation values of a given operator AA among normalized pure states, which belong to the nucleus of an auxiliary operator ZZ. This notion proves to be applicable to investigate models of quantum noise with block-diagonal structure of the corresponding Kraus operators. The problem of constructing a suitable quantum error correction code for this model can be restated as a geometric problem of finding intersection points of certain sets in the complex plane. This technique, worked out in the case of two-qubit systems, can be generalized for larger dimensions.

Keywords

Cite

@article{arxiv.1610.00930,
  title  = {Nuclear Numerical Range and Quantum Error Correction Codes for non-unitary noise models},
  author = {Patryk Lipka-Bartosik and Karol Życzkowski},
  journal= {arXiv preprint arXiv:1610.00930},
  year   = {2017}
}

Comments

22 pages, 3 figures

R2 v1 2026-06-22T16:09:55.318Z