Quantum measurement bounds beyond the uncertainty relations.
نویسندگان
چکیده
In quantum mechanics, the Heisenberg uncertainty relations and the Cramér-Rao inequalities typically limit the precision in the estimation of a parameter through the standard deviation of a conjugate observable. Here we extend these relations by giving a bound to the precision of a parameter in terms of the expectation value of the conjugate observable. This has both foundational and practical consequences: in quantum optics it resolves a controversy over which is the ultimate precision in interferometry.
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ورودعنوان ژورنال:
- Physical review letters
دوره 108 26 شماره
صفحات -
تاریخ انتشار 2012