Corpus ID: 222140944

A Generalized Measure of Quantum Fisher Information

  title={A Generalized Measure of Quantum Fisher Information},
  author={A. Sone and M. Cerezo and J. Beckey and Patrick J. Coles},
  journal={arXiv: Quantum Physics},
In this work, we present an efficiently computable lower bound on the quantum Fisher information (QFI). This bound itself is of interest, as we show that it satisfies the canonical criteria of a QFI measure. Specifically, it is essentially a QFI measure for sub-normalized states, and hence it generalizes the standard QFI in this sense. Our bound employs the generalized fidelity applied to the truncated state, which is constructed via the $m$ largest eigenvalues and their corresponding… Expand

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