Exponentially enhanced quantum metrology.
نویسندگان
چکیده
We show that when a suitable entanglement-generating unitary operator depending on a parameter is applied on N qubits in parallel, a precision of the order of 2(-N) in estimating the parameter may be achieved. This exponentially improves the precision achievable in classical and in quantum nonentangling strategies.
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ورودعنوان ژورنال:
- Physical review letters
دوره 100 22 شماره
صفحات -
تاریخ انتشار 2008