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Related papers: Quantum Coherence Dispersion

200 papers

Macroscopic behavior such as the lack of interference patterns has been attributed to "decoherence", a word with several possible definitions such as (1) the loss of off-diagonal density matrix elements, (2) the flow of information to the…

Quantum Physics · Physics 2015-05-30 Patrick J. Coles

Quantifying coherence is a key task in both quantum mechanical theory and practical applications. Here, a reliable quantum coherence measure is presented by utilizing the quantum skew information of the state of interest subject to a…

Quantum Physics · Physics 2017-05-03 Chang-shui Yu

The non-increasing behavior of quantum coherence during any incoherent quantum process such as an incoherent quantum channel occurring in a noisy environment is a general property of quantum coherence. We address that the concatenation of…

Quantum Physics · Physics 2021-12-22 Durgun Duran

Establishing quantum correlations between two remote parties by sending an information carrier is an essential step of many protocols in quantum information processing. We obtain trade-off relations between discords and coherence within a…

Quantum Physics · Physics 2022-03-25 Zhi-Xiang Jin , Xianqing Li-Jost , Shao-Ming Fei , Cong-Feng Qiao

We explore methods to generate quantum coherence through unitary evolutions, by introducing and studying the coherence generating capacity of Hamiltonians. This quantity is defined as the maximum derivative of coherence that can be achieved…

Quantum Physics · Physics 2024-08-13 Manfredi Scalici , Moein Naseri , Alexander Streltsov

We establish two complementarity relations for the relative entropy of coherence in quantum information processing, i.e., quantum dense coding and teleportation. We first give an uncertaintylike expression relating local quantum coherence…

Quantum Physics · Physics 2017-02-22 F. Pan , L. Qiu , Z. Liu

The concept of coherence is one of cornerstones in physics. The development of quantum information science has lead to renewed interest in properly approaching the coherence at the quantum level. Various measures could be proposed to…

Quantum Physics · Physics 2016-04-06 Alexey E. Rastegin

This paper introduces a novel approach to probabilistic deep learning, kernel density matrices, which provide a simpler yet effective mechanism for representing joint probability distributions of both continuous and discrete random…

Machine Learning · Computer Science 2024-05-01 Fabio A. González , Raúl Ramos-Pollán , Joseph A. Gallego-Mejia

We study decoherence in a simple quantum mechanical model using two approaches. Firstly, we follow the conventional approach to decoherence where one is interested in solving the reduced density matrix from the perturbative master equation.…

Quantum Physics · Physics 2015-05-20 Jurjen F. Koksma , Tomislav Prokopec , Michael G. Schmidt

Quantum coherence and distributed correlations among subparties are often considered as separate, although operationally linked to each other, properties of a quantum state. Here, we propose a measure able to quantify the contributions…

Quantum Physics · Physics 2018-12-11 Gian Luca Giorgi , Roberta Zambrini

Quantum coherence plays an important role in quantum information protocols that provide an advantage over classical information processing. The amount of coherence that can exist between two orthogonal subspaces is limited by the positivity…

Quantum Physics · Physics 2019-11-25 Tristan Kraft , Marco Piani

Quantum coherence is the most fundamental feature of quantum mechanics. The usual understanding of it depends on the choice of the basis, that is, the coherence of the same quantum state is different within different reference framework. To…

Quantum Physics · Physics 2017-04-17 Chang-shui Yu , Yi-ren Yang , Bao-qing Guo

The dynamical evolution of a quantum register of arbitrary length coupled to an environment of arbitrary coherence length is predicted within a relevant model of decoherence. The results are reported for quantum bits (qubits) coupling…

Quantum Physics · Physics 2009-11-07 John H. Reina , Luis Quiroga , Neil F. Johnson

Quantum coherence is a fundamental common trait of quantum phenomena, from the interference of matter waves to quantum degeneracy of identical particles. Despite its importance, estimating and measuring quantum coherence in generic, mixed…

Statistical Mechanics · Physics 2016-08-17 Irénée Frérot , Tommaso Roscilde

Incoherence in the controlled Hamiltonian is an important limitation on the precision of coherent control in quantum information processing. Incoherence can typically be modelled as a distribution of unitary processes arising from slowly…

Quantum Physics · Physics 2009-11-10 N. Boulant , S. Furuta , J. Emerson , T. F. Havel , D. G. Cory

Various measures have been suggested recently for quantifying the coherence of a quantum state with respect to a given basis. We first use two of these, the l_1-norm and relative entropy measures, to investigate tradeoffs between the…

Quantum Physics · Physics 2015-10-08 Shuming Cheng , Michael J. W. Hall

We derive upper bounds for Hilbert-Schmidt's quantum coherence of general states of a $d$-level quantum system, a qudit, in terms of its incoherent uncertainty, with the latter quantified using the linear and von Neumann's entropies of the…

Quantum Physics · Physics 2020-07-22 Marcos L. W. Basso , Diego S. S. Chrysosthemos , Jonas Maziero

We clarify different definitions of the density matrix by proposing the use of different names, the full density matrix for a single-closed quantum system, the compressed density matrix for the averaged single molecule state from an…

Quantum Physics · Physics 2007-05-23 Gui Lu Long , Yi-Fan Zhou , Jia-Qi Jin , Yang Sun , Hai-Woong Lee

Quantum entanglement and coherence are two fundamental resources for quantum information processing. Recent results clearly demonstrate their relevance in quantum technological tasks, including quantum communication and quantum algorithms.…

Quantum Physics · Physics 2018-04-16 Anurag Anshu , Rahul Jain , Alexander Streltsov

Quantum entanglement is a form of correlation between quantum particles that has now become a crucial part in quantum information and communication science. For example, it has been shown to enable or enhance quantum processing tasks such…

Quantum Physics · Physics 2020-03-20 Tanjung Krisnanda