Fluctuation of information content and the optimum capacity for bosonic transport
Department of Physics Engineering, Faculty of Engineering, Mie University, 514-8507, Tsu, Mie, Japan
Accepted: 5 January 2021
Published online: 13 April 2021
We discuss the optimum communication capacity of bosonic information carriers propagating through a tunnel junction. Based on the multi-contour Keldysh Green function, we evaluate the information generating function, or the Rényi entanglement entropy, of the reduced density matrix subjected to the constraint of local heat quantity in the steady state. The Rényi entanglement entropy of order zero is the partition function, which exponentially depends on the optimum capacity. For the perfect transmission, the self-information and the local heat quantity, i.e., the energy of signals, are perfectly linearly correlated. The water-filling theorem is recovered in the wave-like regime.
© The Author(s), under exclusive licence to EDP Sciences, Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021