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Superdense coding of quantum states

Aram Harrow·Patrick Hayden·Debbie Leung
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Abstract

We describe a method to non-obliviously communicate a 2l-qubit quantum state by physically transmitting l+o(l) qubits of communication, and by consuming l ebits of entanglement and some shared random bits. In the non-oblivious scenario, the sender has a classical description of the state to be communicated. Our method can be used to communicate states that are pure or entangled with the sender's system; l+o(l) and 3l+o(l) shared random bits are sufficient respectively.

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Aram Harrow, Patrick Hayden, Debbie Leung. 2004-04-30. Superdense coding of quantum states. https://doi.org/10.1103/physrevlett.92.187901

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