Unsharp measurements and joint measurability

  title={Unsharp measurements and joint measurability},
  author={H. S. Karthik and A. R. Usha Devi and A. K. Rajagopal},
  journal={arXiv: Quantum Physics},
We give an overview of joint unsharp measurements of non-commuting observables using positive operator valued measures (POVMs). We exemplify the role played by joint measurability of POVMs in entropic uncertainty relation for Alice's pair of non-commuting observables in the presence of Bob's entangled quantum memory. We show that Bob should record the outcomes of incompatible (non-jointly measurable) POVMs in his quantum memory so as to beat the entropic uncertainty bound. In other words, in… 
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