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Related papers: Memory effects in a Markov chain dephasing channel

200 papers

Memory effects can be studied through a conditional past-future correlation, which measures departure with respect to a conditional past-future independence valid in a memoryless Markovian regime. In a quantum regime this property leads to…

Quantum Physics · Physics 2019-06-05 Adrian A. Budini

We propose a protocol for countering the effects of dephasing in quantum state transfer over a noisy spin channel weakly coupled to the sender and receiver qubits. Our protocol, based on performing regular global measurements on the…

Quantum Physics · Physics 2015-10-26 Abolfazl Bayat , Yasser Omar

We investigate the classical capacity of two quantum channels with memory: a periodic channel with depolarizing channel branches, and a convex combination of depolarizing channels. We prove that the capacity is additive in both cases. As a…

Quantum Physics · Physics 2009-11-13 Tony Dorlas , Ciara Morgan

We consider the problem of energy transport in a chain of coupled dissipative quantum systems in the presence of non-Markovian dephasing. We use a model of non-Markovianity which is experimentally realizable in the context of controlled…

We theoretically study the dynamical dephasing of a quantum two level system interacting with an environment exhibiting non-Markovian random telegraph fluctuations. The time evolution of the conditional probability of the environmental…

Quantum Physics · Physics 2020-01-10 Xiangji Cai

We provide a model to study memory effects in quantum Gaussian channels with additive classical noise over an arbitrary number of uses. The correlation among different uses is introduced by contiguous two-mode interactions. Numerical…

Quantum Physics · Physics 2007-05-23 Giovanna Ruggeri , Stefano Mancini

We probe dephasing mechanisms within a quantum network node consisting of a single nitrogen-vacancy centre electron spin that is hyperfine coupled to surrounding $^{13} \text{C}$ nuclear-spin quantum memories. Previous studies have analysed…

Quantum Physics · Physics 2018-06-27 N. Kalb , P. C. Humphreys , J. J. Slim , R. Hanson

We show that long-term memory effects, present in the chaotic dispersion process generated by a meandering jet model, can be nonetheless taken into account by a first order Markov process, provided that the states of the phase space…

Chaotic Dynamics · Physics 2015-06-26 Guglielmo Lacorata , Ruben A. Pasmanter , Angelo Vulpiani

The possibility of stochastic resonance of a quantum channel and hence the noise enhanced capacity of the channel is explored by considering the depolarizing channel. The fidelity of the channel is also considered. Although there is no…

Statistical Mechanics · Physics 2007-05-23 Julian Juhi-Lian Ting

We investigate the performance of the charger-mediated quantum battery modeled by a two-qubit system. One of the qubits acts as the battery and the other acts as the charger which is subjected to a reservoir. We derived the time-local…

Quantum Physics · Physics 2026-02-17 Yu Wang , Jiasen Jin

Probabilistic error cancellation is an attempt to reverse the effect of dissipative noise channels on quantum computers by applying unphysical channels after the execution of a quantum algorithm on noisy hardware. We investigate on general…

The quantum capacity of a quantum channel captures its capability for noiseless quantum communication. It lies at the heart of quantum information theory. Unfortunately, our poor understanding of nonadditivity of coherent information makes…

Quantum Physics · Physics 2018-12-07 Felix Leditzky , Debbie Leung , Graeme Smith

We analyze the depth of the memory of quantum memory channels generated by a fixed unitary transformation describing the interaction between the principal system and internal degrees of freedom of the process device. We investigate the…

Quantum Physics · Physics 2009-08-03 Mário Ziman , Tomáš Rybár

Memory effect of non-Markovian dynamics in open quantum systems is often believed to be beneficial for quantum information processing. In this work, we employ an experimentally controllable two-photon open system, with one photon…

Quantum Physics · Physics 2015-03-18 Zhen-Yu Xu , Chen Liu , Shunlong Luo , Shiqun Zhu

We consider the discrete memoryless degraded broadcast channels with feedback. We prove that the error probability of decoding tends to one exponentially for rates outside the capacity region and derive an explicit lower bound of this…

Information Theory · Computer Science 2015-04-24 Yasutada Oohama

The theory of quantum error correction is a cornerstone of quantum information processing. It shows that quantum data can be protected against decoherence effects, which otherwise would render many of the new quantum applications…

Quantum Physics · Physics 2009-11-07 M. Keyl , R. F. Werner

Time-varying quantum channels are essential for modeling realistic quantum systems with evolving noise properties. Here, we consider Gaussian lossy channels varying from one use to another and we employ neural networks to classify, regress,…

Quantum systems are affected by interactions with their environments, causing decoherence through two processes: pure dephasing and energy relaxation. For quantum information processing it is important to increase the coherence time of…

Quantum Physics · Physics 2018-03-21 Roberto Stassi , Franco Nori

A transform that is universally polarizing over a set of channels with memory is presented. Memory may be present in both the input to the channel and the channel itself. Both the encoder and the decoder are aware of the input distribution,…

Information Theory · Computer Science 2024-09-13 Boaz Shuval , Ido Tal

We study the effects of diffusion on a $\Lambda$-gradient echo memory, which is a coherent optical quantum memory using thermal gases. The efficiency of this memory is high for short storage time, but decreases exponentially due to…

Quantum Physics · Physics 2015-06-15 X. -W. Luo , J. J. Hope , B. Hillman , T. M. Stace