Eur. Phys. J. D (2012) 66: 147
https://doi.org/10.1140/epjd/e2012-20593-7

Regular Article

Transmission of classical and quantum information through a quantum memory channel with damping

¹ CNR-IMM-Uos Catania (Università), Consiglio Nazionale delle Ricerche, Via Santa Sofia 64, 95123 Catania, Italy
² Dipartimento di Fisica e Astronomia, Università degli Studi Catania, c/o Viale Andrea Doria 6, Ed. 10, 95125 Catania, Italy
³ CNISM, CNR-INFM & Center for Nonlinear and Complex Systems, Università degli Studi dell’Insubria, Via Valleggio 11, 22100 Como, Italy
⁴ Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milano, Italy
⁵ Centro Siciliano di Fisica Nucleare e di Struttura della Materia (CSFNSM), Viale S. Sofia 64, 95123 Catania, Italy

^a e-mail: adarrigo@dmfci.unict.it

Received: 13 October 2011
Received in final form: 27 March 2012
Published online: 13 June 2012

Abstract

We consider the transfer of classical and quantum information through a memory amplitude damping channel. Such a quantum channel is modeled as a damped harmonic oscillator, the interaction between the information carriers – a train of qubits – and the oscillator being of the Jaynes-Cummings kind. We prove that this memory channel is forgetful, so that quantum coding theorems hold for its capacities. We analyze entropic quantities relative to two uses of this channel. We show that memory effects improve the channel aptitude to transmit both classical and quantum information, and we investigate the mechanism by which memory acts in changing the channel transmission properties.