Single qubit estimation from repeated unsharp measurements
نویسندگان
چکیده
منابع مشابه
Single Qubit Estimation from Repeated Unsharp Measurements
When estimating an unknown single pure qubit state, the optimum fidelity is 2/3. As it is well known, the value 2/3 can be achieved in one step, by a single ideal measurement of the polarization along a random direction. I analyze the opposite strategy which is the long sequence of unsharp polarization measurements. The evolution of the qubit under the influence of repeated measurements is quit...
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ژورنال
عنوان ژورنال: Fortschritte der Physik
سال: 2003
ISSN: 0015-8208,1521-3978
DOI: 10.1002/prop.200310009