Information Gain versus State Disturbance for a Single Qubit
نویسندگان
چکیده
منابع مشابه
Information Gain vs. State Disturbance in Quantum Theory
The engine that powers quantum cryptography is the principle that there are no physical means for gathering information about the identity of a quantum system’s state (when it is known to be prepared in one of a set of nonorthogonal states) without disturbing the system in a statistically detectable way. This situation is often mistakenly described as a consequence of the “Heisenberg uncertaint...
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When discriminating between two pure quantum states, there exists a quantitative tradeoff between the information retrieved by the measurement and the disturbance caused on the unknown state. We derive the optimal tradeoff and provide the corresponding quantummeasurement. Such an optimal measurement smoothly interpolates between the two limiting cases of maximal information extraction and no me...
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ژورنال
عنوان ژورنال: Open Systems & Information Dynamics
سال: 2006
ISSN: 1230-1612,1793-7191
DOI: 10.1007/s11080-006-7263-8