Are All Noisy Quantum States Obtained from Pure Ones?
نویسندگان
چکیده
منابع مشابه
Are all noisy quantum states obtained from pure ones?
We ask what type of mixed quantum states can arise when a number of separated parties start by sharing a pure quantum state and then this pure state becomes contaminated by noise. We show that not all mixed states arise in this way. This is even the case if the separated parties actively try to degrade their initial pure state by arbitrary local actions and classical communication.
متن کاملua nt - p h / 01 04 06 5 v 1 1 2 A pr 2 00 1 Are all noisy quantum states obtained from pure ones ?
Density matrices and the question of their entanglement have been studied very intensively during the last few years [1]. However the question of how these density matrices arise in the first place has received much less attention. It has been tacitly assumed that density matrices arise when a number of parties, separated in space, start by sharing a pure state, and then this state gets contami...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2001
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.87.237901