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Related papers: Fidelity of Gaussian channels

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We find the maximum rate achievable in the private communication over a bosonic quantum channel with a fully Gaussian protocol based on optimal single-mode Gaussian measurements. This rate establishes a lower bound on the secret rate…

Quantum Physics · Physics 2025-12-18 Giuseppe Ortolano , Stefano Pirandola , Leonardo Banchi

We present a scalable method for learning local quantum channels using local expectation values measured on a single state -- their steady state. Our method is inspired by the algorithms for learning local Hamiltonians from their ground…

Quantum Physics · Physics 2024-07-12 Yigal Ilin , Itai Arad

We study the fidelity of quantum teleportation for the situation in which quantum logic gates are used to provide the long distance entanglement required in the protocol, and where the effect of a noisy environment is modeled by means of a…

Quantum Physics · Physics 2007-05-23 Gabriel G Carlo , Giuliano Benenti , Giulio Casati

We study the quantum capacity of continuous variable dephasing channel, which is a notable example of non-Gaussian quantum channel. We prove that a single letter formula applies. We then consider input energy restriction and show that by…

Quantum Physics · Physics 2021-03-24 Amir Arqand , Laleh Memarzadeh , Stefano Mancini

The Glauber-Sudarshan diagonal `weight' function provides a natural divide between the quantum-optical notion of classical and nonclassical states of continuous variables systems. Based on this demarcation, a channel is said to be…

Quantum Physics · Physics 2016-04-28 Krishna Kumar Sabapathy

Quantum information characteristics, such as quantum mutual information, loss, noise and coherent information are explicitly calculated for Bosonic attenuation/amplification channel with input Gaussian state. The coherent information is…

Quantum Physics · Physics 2007-05-23 Alexander S. Holevo

The nonnegative Wigner function of all quantum states involved in teleportation of Gaussian states using the standard continuous-variable teleportation protocol means that there is a local realistic phase-space description of the process.…

Quantum Physics · Physics 2009-11-10 Carlton M. Caves , Krzysztof Wodkiewicz

Quantum fidelity estimation is essential for benchmarking quantum states and processes on noisy quantum devices. While stabilizer operations form the foundation of fault-tolerant quantum computing, non-stabilizer resources further enable…

Quantum Physics · Physics 2025-06-17 Zhiping Liu , Kun Wang , Xin Wang

We give a criterion to differentiate between dissipative and diffusive quantum operations. It is based on the classical idea that dissipative processes contract volumes in phase space. We define a quantity that can be regarded as ``quantum…

Quantum Physics · Physics 2010-03-31 Ignacio Garcia-Mata , Marcos Saraceno , Maria Elena Spina , Gabriel Carlo

Even though measurement results obtained in the real world are generally both noisy and continuous, quantum measurement theory tends to emphasize the ideal limit of perfect precision and quantized measurement results. In this article, a…

Quantum Physics · Physics 2008-12-18 Holger F. Hofmann

The minimum mean square error of the estimation of a non Gaussian signal where observed from an additive white Gaussian noise channel's output, is analyzed. First, a quite general time-continuous channel model is assumed for which the…

Information Theory · Computer Science 2010-02-04 Jacob Binia

To model printing noise a binary noisy channel and a set of controlled gates are introduced. The channel input is an image created by a halftoning algorithm and its output is the printed picture. Using this channel robustness to noise…

Other Computer Science · Computer Science 2015-03-19 V. N. Gorbachev , E. S. Yakovleva

We relate gate fidelities of experimentally realized quantum operations to the broadcasting property of their ideal operations, and show that the more parties a given quantum operation can broadcast to, the higher gate fidelities of its…

Quantum Physics · Physics 2011-06-30 Hyang-Tag Lim , Young-Sik Ra , Yong-Su Kim , Yoon-Ho Kim , Joonwoo Bae

We provide a simple and realistic model to study memory effects in a lossy bosonic quantum channel over arbitrary number of uses. The noise correlation among different uses is introduced by contiguous modes interactions which results in an…

Quantum Physics · Physics 2009-11-13 O. V. Pilyavets , V. G. Zborovskii , S. Mancini

We derive fidelity benchmarks for the quantum storage and teleportation of squeezed states of continuous variable systems, for input ensembles where the degree of squeezing $s$ is fixed, no information about its orientation in phase space…

Quantum Physics · Physics 2009-11-13 M. Owari , M. B. Plenio , E. S. Polzik , A. Serafini , M. M. Wolf

We define the quantum zero-error capacity, a new kind of classical capacity of a noisy quantum channel. Moreover, the necessary requirement for which a quantum channel has zero-error capacity greater than zero is also given.

Quantum Physics · Physics 2007-05-23 Rex A. C. Medeiros , Francisco M. de Assis

We associate to every quantum channel $T$ acting on a Hilbert space $\mathcal{H}$ a pair of Hamiltonian operators over the symmetric subspace of $\mathcal{H}^{\otimes 2}$. The expectation values of these Hamiltonians over symmetric product…

Quantum Physics · Physics 2007-05-23 Paolo Zanardi , Daniel Lidar

The fidelity of a quantum transformation is strongly linked with the prior partial information of the state to be transformed. We illustrate this interesting point by proposing and demonstrating the superior cloning of coherent states with…

Quantum Physics · Physics 2009-11-13 Metin Sabuncu , Gerd Leuchs , Ulrik L. Andersen

The random purification channel, which, given $n$ copies of an unknown mixed state $\rho$, prepares $n$ copies of an associated random purification, has proved to be an extremely valuable tool in quantum information theory. In this work, we…

Quantum Physics · Physics 2025-12-19 Francesco Anna Mele , Filippo Girardi , Senrui Chen , Marco Fanizza , Ludovico Lami

The arbitrarily varying channel (AVC) is a conservative way of modeling an unknown interference, and the corresponding capacity results are pessimistic. We reconsider the Gaussian AVC by relaxing the classical model and thereby weakening…

Information Theory · Computer Science 2012-09-14 Anand D. Sarwate , Michael Gastpar
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