Quantum Polarization of Qudit Channels
- URL: http://arxiv.org/abs/2101.10194v3
- Date: Mon, 3 May 2021 14:56:26 GMT
- Title: Quantum Polarization of Qudit Channels
- Authors: Ashutosh Goswami, Mehdi Mhalla, Valentin Savin
- Abstract summary: We provide a generalization of quantum polar codes to quantum channels with qudit-input.
We show how to decode the proposed quantum polar codes on Pauli qudit channels.
- Score: 5.607676459156789
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We provide a generalization of quantum polar codes to quantum channels with
qudit-input, achieving the symmetric coherent information of the channel. Our
scheme relies on a channel combining and splitting construction, where a
two-qudit unitary randomly chosen from a unitary 2-design is used to combine
two instances of a qudit-input channel. The inputs to the synthesized bad
channels are frozen by sharing EPR pairs between the sender and the receiver,
so our scheme is entanglement assisted. Using the fact that the generalized
two-qudit Clifford group forms a unitary 2-design, we conclude that the channel
combining operation can be chosen from this set. Moreover, we show that
polarization also happens for a much smaller subset of two-qudit Cliffords,
which is not a unitary 2-design. Finally, we show how to decode the proposed
quantum polar codes on Pauli qudit channels.
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