Square-root measurement for quantum symmetric mixed state signal
نویسندگان
چکیده
A certain class of mixed states artificially constructed that is used in quantum cryptography is crucial for representation of signals. This correspondence shows that the square-root measurement gives the optimal measurement for such a class of mixed states.
منابع مشابه
Minimum-error discrimination between symmetric mixed quantum states
We provide a solution of finding optimal measurement strategy for distinguishing between symmetric mixed quantum states. It is assumed that the matrix elements of at least one of the symmetric quantum states are all real and nonnegative in the basis of the eigenstates of the symmetry operator. Typeset using REVTEX ∗[email protected] †[email protected] 1
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ورودعنوان ژورنال:
- IEEE Trans. Information Theory
دوره 49 شماره
صفحات -
تاریخ انتشار 2003