State-independent purity and fidelity of quantum operations

  title={State-independent purity and fidelity of quantum operations},
  author={Fan-Zhen Kong and Xiao-Lan Zong and Ming Yang and Zhuo-Liang Cao},
  journal={Laser Physics Letters},
The purity and fidelity of quantum operations are of great importance in characterizing the quality of quantum operations. The currently available definitions of the purity and fidelity of quantum operations are based on the average over all possible input pure quantum states, i.e. they are state-dependent (SD). In this paper, without resorting to quantum states, we define the state-independent (SI) purity and fidelity of a general quantum operation (evolution) in virtue of a new density matrix… Expand
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