English
Related papers

Related papers: Capacities of lossy bosonic memory channels

200 papers

We prove the multimode conditional quantum Entropy Power Inequality for bosonic quantum systems. This inequality determines the minimum conditional von Neumann entropy of the output of the most general linear mixing of bosonic quantum modes…

Quantum Physics · Physics 2025-07-08 Alessandro Falco , Giacomo De Palma

We address the estimation of the loss parameter of a bosonic channel probed by Gaussian signals. We derive the ultimate quantum bound on precision and show that no improvement may be obtained by having access to the environment degrees of…

Quantum Physics · Physics 2009-11-13 Alex Monras , Matteo G. A. Paris

We investigate the quantum capacity of noisy quantum channels which can be represented by coupling a system to an effectively small environment. A capacity formula is derived for all cases where both system and environment are…

Quantum Physics · Physics 2009-11-13 Michael M. Wolf , David Perez-Garcia

A generic quantum channel can be represented in terms of a unitary interaction between the information-carrying system and a noisy environment. Here, the minimal number of quantum Gaussian environmental modes required to provide a unitary…

Quantum Physics · Physics 2015-05-19 Filippo Caruso , Jens Eisert , Vittorio Giovannetti , Alexander S. Holevo

We present a method to detect lower bounds to the classical capacity of quantum communication channels by means of few local measurements (i.e. without complete process tomography), reconstruction of sets of conditional probabilities, and…

Quantum Physics · Physics 2019-08-30 Chiara Macchiavello , Massimiliano F. Sacchi

In most studies of the capacity of quantum channels, it is assumed that the errors in each use of the channel are independent. However, recent work has begun to investigate the effects of memory or correlations in the error, and has led to…

Quantum Physics · Physics 2008-05-10 M. B. Plenio , S. Virmani

The capacity of time-varying channels with periodic feedback at the transmitter is evaluated. It is assumed that the channel state information is perfectly known at the receiver and is fed back to the transmitter at the regular…

Information Theory · Computer Science 2007-07-13 Mehdi Ansari Sadrabadi , Mohammad Ali Maddah-Ali , Amir K. Khandani

A quantum message is encoded into $N$ storage nodes (quantum systems $Q_1\dots Q_N$) with assistance from $N_B$ maximally entangled bi-partite quantum systems $A_1B_1, \dots, A_{N_B}B_{N_B}$, that are prepared in advance such that $B_1\dots…

Information Theory · Computer Science 2025-12-09 Hua Sun , Syed A. Jafar

An expression is derived characterizing the set of admissible rate pairs for simultaneous transmission of classical and quantum information over a given quantum channel, generalizing both the classical and quantum capacities of the channel.…

Quantum Physics · Physics 2007-05-23 I. Devetak , P. W. Shor

A model of quantum noisy channel with input encoding by a classical random vector is described. An equation of optimality is derived to determine a complete set of wave functions describing quantum decodings based on quasi-measurements…

Quantum Physics · Physics 2007-05-23 V. P. Belavkin , R. L. Stratonovich

Dephasing is a prominent noise mechanism that afflicts quantum information carriers, and it is one of the main challenges towards realizing useful quantum computation, communication, and sensing. Here we consider discrimination and…

Quantum Physics · Physics 2024-06-11 Zixin Huang , Ludovico Lami , Mark M. Wilde

Quantum memory systems are vital in quantum information processing for dependable storage and retrieval of quantum states. Inspired by classical reliability theories that synthesize reliable computing systems from unreliable components, we…

Quantum Physics · Physics 2025-12-10 Anuj K. Nayak , Eric Chitambar , Lav R. Varshney

The long-standing conjectures of the optimality of Gaussian inputs for Gaussian channel and Gaussian additivity are solved for a broad class of covariant or contravariant Bosonic Gaussian channels (which includes in particular thermal,…

Quantum Physics · Physics 2015-03-04 V. Giovannetti , A. S. Holevo , R. Garcia-Patron

We consider a setting where a stream of qubits is processed sequentially. We derive fundamental limits on the rate at which classical information can be transmitted using qubits that decohere as they wait to be processed. Specifically, we…

Information Theory · Computer Science 2020-08-11 Prabha Mandayam , Krishna Jagannathan , Avhishek Chatterjee

A popular approach to learning encoders for lossy compression is to use additive uniform noise during training as a differentiable approximation to test-time quantization. We demonstrate that a uniform noise channel can also be implemented…

Machine Learning · Statistics 2020-10-22 Eirikur Agustsson , Lucas Theis

Entanglement-breaking channels (equivalently, measure-and-prepare channels) are an important class of quantum operations noted for their ability to destroy multipartite spatial quantum correlations. Inspired by this property, they have also…

Quantum Physics · Physics 2025-12-22 Lucas B. Vieira , Huan-Yu Ku , Costantino Budroni

In Shannon information theory the capacity of a memoryless communication channel cannot be increased by the use of feedback from receiver to sender. In this paper the use of classical feedback is shown to provide no increase in the…

Quantum Physics · Physics 2007-05-23 Garry Bowen , Rajagopal Nagarajan

The set of Multi-level Amplitude Damping (MAD) quantum channels is introduced as a generalization of the standard qubit Amplitude Damping Channel to quantum systems of finite dimension $d$. In the special case of $d=3$, by exploiting…

Quantum Physics · Physics 2021-03-03 Stefano Chessa , Vittorio Giovannetti

We show an experimental procedure to certify the classical capacity for noisy qubit channels. The method makes use of a fixed bipartite entangled state, where the system qubit is sent to the channel input and the set of local measurements…

We present a comprehensive characterization of the interconnections between single-mode, phaseinsensitive Gaussian Bosonic Channels resulting from channel concatenation. This characterization enables us to identify, in the parameter space…

Quantum Physics · Physics 2024-09-27 Farzad Kianvash , Marco Fanizza , Vittorio Giovannetti