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Title: Quantum capacity and codes for the bosonic loss-dephasing channel
Bosonic qubits encoded in continuous-variable systems provide a promising alternative to two-level qubits for quantum computation and communication. So far, photon loss has been the dominant source of errors in bosonic qubits, but the significant reduction of photon loss in recent bosonic qubit experiments suggests that dephasing errors should also be considered. However, a detailed understanding of the combined photon loss and dephasing channel is lacking. Here, we show that, unlike its constituent parts, the combined loss-dephasing channel is non-degradable, pointing towards a richer structure of this channel. We provide bounds for the capacity of the loss-dephasing channel and use numerical optimization to find optimal single-mode codes for a wide range of error rates.  more » « less
Award ID(s):
1936118 2137642
PAR ID:
10384653
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Quantum
Volume:
6
ISSN:
2521-327X
Page Range / eLocation ID:
821
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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