Variance-based uncertainty relation for incompatible observers

نویسندگان

  • Xiao Zheng
  • Guo-Feng Zhang
چکیده

Based on mixedness definition as ( ), we obtain a new variance-based uncertainty equality along with an inequality for Hermitian operators of a single-qubit system. The obtained uncertainty equality can be used as a measure of the system mixedness. A qubit system with feedback control is also exploited to demonstrate the new uncertainty. PACS number(s): 03.65.Yz; 03.65.Ud

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عنوان ژورنال:
  • Quantum Information Processing

دوره 16  شماره 

صفحات  -

تاریخ انتشار 2017