A class of adaptive decoders (ADs) for coherent-state sequences is studied, including in particular the most common technology for optical-signal processing, e.g., interferometers, coherent displacements, and photon-counting detectors. More generally we consider ADs comprising adaptive procedures based on passive multimode Gaussian unitaries and arbitrary single-mode destructivemeasurements. For classical communication on quantum phase-insensitive Gaussian channels with a coherent-state encoding, we show that the AD's optimal information transmission rate is not greater than that of a single-mode decoder. Our result also implies that the ultimate classical capacity of quantum phase-insensitive Gaussian channels is unlikely to be achieved with the considered class of ADs.
Rosati, M., Mari, A., Giovannetti, V. (2017). Capacity of coherent-state adaptive decoders with interferometry and single-mode detectors. PHYSICAL REVIEW A, 96(1) [10.1103/physreva.96.012317].
Capacity of coherent-state adaptive decoders with interferometry and single-mode detectors
Rosati, Matteo
;
2017-01-01
Abstract
A class of adaptive decoders (ADs) for coherent-state sequences is studied, including in particular the most common technology for optical-signal processing, e.g., interferometers, coherent displacements, and photon-counting detectors. More generally we consider ADs comprising adaptive procedures based on passive multimode Gaussian unitaries and arbitrary single-mode destructivemeasurements. For classical communication on quantum phase-insensitive Gaussian channels with a coherent-state encoding, we show that the AD's optimal information transmission rate is not greater than that of a single-mode decoder. Our result also implies that the ultimate classical capacity of quantum phase-insensitive Gaussian channels is unlikely to be achieved with the considered class of ADs.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.