TY - JOUR
T1 - Demonstration of a quantum advantage by a joint detection receiver for optical communication using quantum belief propagation on a trapped-ion device
AU - Delaney, Conor
AU - Seshadreesan, Kaushik P.
AU - Maccormack, Ian
AU - Galda, Alexey
AU - Guha, Saikat
AU - Narang, Prineha
N1 - Funding Information:
This work is supported by Air Force STTR Grants No. FA8750-20-P-1721 and No. FA8750-20-P-1704. K.P.S. and S.G. acknowledge support from the National Science Foundation (NSF) project “CIF: Medium: Iterative Quantum LDPC Decoders,” Award No. 1855879, and the Office of Naval Research (ONR) MURI project on “Optical Computing,” Grant No. N00014-14-1-0505. K.P.S. acknowledges NSF Grant No. 2204985. The authors gratefully acknowledge the entire Honeywell Quantum Solutions team, especially Dr. B. Neyenhuis, for helpful discussions and support in running these experiments. The authors thank Dr. M. Fanto (AFRL) as well as S. Willis and Dr. N. Aggarwal (Aliro Technologies) for helpful feedback on the work and manuscript. K.P.S. thanks Dr. N. Rengaswamy for helpful discussions.
Publisher Copyright:
© 2022 American Physical Society.
PY - 2022/9
Y1 - 2022/9
N2 - Demonstrations of quantum advantage have largely focused on computational speedups and on quantum simulation of many-body physics, limited by fidelity and the capability of current devices. Discriminating laser-pulse-modulated classical-communication code words at the minimum allowable probability of error using universal-quantum processing presents a promising parallel direction, one that is of both fundamental importance in quantum state discrimination and technological relevance in deep-space laser communications. Here we present an experimental realization of a quantum joint detection receiver for binary phase shift keying modulated code words of a 3-bit linear tree code using a recently proposed quantum algorithm: belief propagation with quantum messages. The receiver, translated to a quantum circuit, was experimentally implemented on a trapped-ion device - the recently released Honeywell LT-1.0 system using Yb+171 ions, which possesses all-to-all connectivity and midcircuit measurement capabilities that are essential to this demonstration. We conclusively realize a previously postulated but hitherto not demonstrated joint quantum detection scheme and provide an experimental framework that surpasses the quantum limit on the minimum average decoding error probability associated with pulse-by-pulse detection in the low-mean-photon-number limit. The full joint detection scheme bridges across photonic and trapped-ion-based quantum information science, mapping the photonic coherent states of the modulation alphabet onto inner product-preserving states of single-ion qubits. Looking ahead, our work opens new avenues in hybrid realizations of quantum-enhanced receivers with applications in astronomy and emerging space-based platforms.
AB - Demonstrations of quantum advantage have largely focused on computational speedups and on quantum simulation of many-body physics, limited by fidelity and the capability of current devices. Discriminating laser-pulse-modulated classical-communication code words at the minimum allowable probability of error using universal-quantum processing presents a promising parallel direction, one that is of both fundamental importance in quantum state discrimination and technological relevance in deep-space laser communications. Here we present an experimental realization of a quantum joint detection receiver for binary phase shift keying modulated code words of a 3-bit linear tree code using a recently proposed quantum algorithm: belief propagation with quantum messages. The receiver, translated to a quantum circuit, was experimentally implemented on a trapped-ion device - the recently released Honeywell LT-1.0 system using Yb+171 ions, which possesses all-to-all connectivity and midcircuit measurement capabilities that are essential to this demonstration. We conclusively realize a previously postulated but hitherto not demonstrated joint quantum detection scheme and provide an experimental framework that surpasses the quantum limit on the minimum average decoding error probability associated with pulse-by-pulse detection in the low-mean-photon-number limit. The full joint detection scheme bridges across photonic and trapped-ion-based quantum information science, mapping the photonic coherent states of the modulation alphabet onto inner product-preserving states of single-ion qubits. Looking ahead, our work opens new avenues in hybrid realizations of quantum-enhanced receivers with applications in astronomy and emerging space-based platforms.
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U2 - 10.1103/PhysRevA.106.032613
DO - 10.1103/PhysRevA.106.032613
M3 - Article
AN - SCOPUS:85139307270
SN - 2469-9926
VL - 106
JO - Physical Review A
JF - Physical Review A
IS - 3
M1 - 032613
ER -