Efficient Quantum Compression for Ensembles of Identically Prepared Mixed States.
نویسندگان
چکیده
We present one-shot compression protocols that optimally encode ensembles of N identically prepared mixed states into O(logN) qubits. In contrast to the case of pure-state ensembles, we find that the number of encoding qubits drops down discontinuously as soon as a nonzero error is tolerated and the spectrum of the states is known with sufficient precision. For qubit ensembles, this feature leads to a 25% saving of memory space. Our compression protocols can be implemented efficiently on a quantum computer.
منابع مشابه
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عنوان ژورنال:
- Physical review letters
دوره 116 8 شماره
صفحات -
تاریخ انتشار 2016