PRA: Quantum information

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Recently published articles in Phys. Rev. A in the Table of Content section "Quantum information"
Updated: 3 min 21 sec ago

Exploration of an augmented set of Leggett-Garg inequalities using a noninvasive continuous-in-time velocity measurement

Mon, 2019-10-21 12:00

Author(s): Shayan-Shawn Majidy, Hemant Katiyar, Galit Anikeeva, Jonathan Halliwell, and Raymond Laflamme

Macroscopic realism (MR) is the view that a system may possess definite properties at any time independent of past or future measurements and may be tested experimentally using the Leggett-Garg inequalities (LGIs). In this work we advance the study of LGIs in two ways using experiments carried out o...


[Phys. Rev. A 100, 042325] Published Mon Oct 21, 2019

Categories: Journals, Physics

Robustness of the concatenated quantum error-correction protocol against noise for channels affected by fluctuation

Mon, 2019-10-21 12:00

Author(s): Long Huang, Xiaohua Wu, and Tao Zhou

In quantum error correction, the description of the noise channel cannot be completely accurate and fluctuation always appears in the noise channel. It is found that when fluctuation of the physical noise channel is considered, the average effective channel is dependent only on the average of the ph...


[Phys. Rev. A 100, 042321] Published Mon Oct 21, 2019

Categories: Journals, Physics

Markovian and non-Markovian dynamics induced by a generic environment

Mon, 2019-10-21 12:00

Author(s): M. Carrera, T. Gorin, and C. Pineda

We study the open dynamics of a quantum two-level system coupled to an environment modeled by random matrices. Using the quantum channel formalism, we investigate different quantum Markovianity measures and criteria. A thorough analysis of the whole parameter space reveals a wide range of different ...


[Phys. Rev. A 100, 042322] Published Mon Oct 21, 2019

Categories: Journals, Physics

One-shot coherence distillation with catalysts

Mon, 2019-10-21 12:00

Author(s): Senrui Chen, Xingjian Zhang, You Zhou, and Qi Zhao

The resource theory of quantum coherence is an important topic in quantum information science. Standard coherence distillation and dilution problems have been thoroughly studied. In this paper, we introduce and study the problem of one-shot coherence distillation with catalysts. In order to distill ...


[Phys. Rev. A 100, 042323] Published Mon Oct 21, 2019

Categories: Journals, Physics

Strong bounds on required resources for quantum channels by local operations and classical communication

Mon, 2019-10-21 12:00

Author(s): Scott M. Cohen

Given a protocol P that implements multipartite quantum channel E by repeated rounds of local operations and classical communication (LOCC), we construct an alternate LOCC protocol for E in no more rounds than P and no more than a fixed, constant number of outcomes for each local measurement, the sa...


[Phys. Rev. A 100, 042324] Published Mon Oct 21, 2019

Categories: Journals, Physics

Broadcasting of quantum correlations in qubit-qudit systems

Fri, 2019-10-18 12:00

Author(s): Rounak Mundra, Dhrumil Patel, Indranil Chakrabarty, Nirman Ganguly, and Sourav Chatterjee

Quantum mechanical properties like entanglement, discord, and coherence act as fundamental resources in various quantum information processing tasks. Consequently, the technique of generating more resources from a few, typically termed as broadcasting, serves as a promising candidate for the design ...


[Phys. Rev. A 100, 042319] Published Fri Oct 18, 2019

Categories: Journals, Physics

Multiparticle quantum walk with a gaslike interaction

Fri, 2019-10-18 12:00

Author(s): Pedro C. S. Costa, Fernando de Melo, and Renato Portugal

We analyze the dynamics of multiparticle discrete-time quantum walk on the two-dimensional lattice, with an interaction inspired on a classical model for gas collision, called the HPP model. In this classical model, the direction of motion changes only when the particles collide head-on, preserving ...


[Phys. Rev. A 100, 042320] Published Fri Oct 18, 2019

Categories: Journals, Physics

Robust holography of the temporal wave function via second-order interference

Thu, 2019-10-17 12:00

Author(s): Yao-Kun Xu, Shi-Hai Sun, Wei-Tao Liu, Ji-Ying Liu, and Ping-Xing Chen

Containing the capacity to record both amplitude and phase information of the light field, holography is of great importance in science and technology. Here, we present robust holography via second-order interference, considering both single-photon states and coherent states. Temporal amplitude and ...


[Phys. Rev. A 100, 042317] Published Thu Oct 17, 2019

Categories: Journals, Physics

Experimental observation of the effect of global phase on optimal times of $\mathrm{SU}(2)$ quantum operations

Wed, 2019-10-16 12:00

Author(s): Ji Bian, Xi Chen, Ran Liu, Zhennan Zhu, Xiaodong Yang, Hui Zhou, and Xinhua Peng

We study the role that the global phase plays in quantum operations. Previous theoretical works suggested that the optimal (minimum) times to realize SU(n) quantum operations with different global phases are generally different. Here, we experimentally constructed two SU(2) operations with different...


[Phys. Rev. A 100, 042315] Published Wed Oct 16, 2019

Categories: Journals, Physics

Deep reinforcement learning for quantum Szilard engine optimization

Wed, 2019-10-16 12:00

Author(s): Vegard B. Sørdal and Joakim Bergli

Machine learning techniques based on artificial neural networks have been successfully applied to solve many problems in science. One of the most interesting domains of machine learning, reinforcement learning, has a natural applicability for optimization problems in physics. In this paper, we use d...


[Phys. Rev. A 100, 042314] Published Wed Oct 16, 2019

Categories: Journals, Physics

Holonomic gates in pseudo-Hermitian quantum systems

Wed, 2019-10-16 12:00

Author(s): Julien Pinske, Lucas Teuber, and Stefan Scheel

The time-dependent pseudo-Hermitian formulation of quantum mechanics allows one to study open system dynamics in analogy to Hermitian quantum systems. In this setting, we show that the notion of holonomic quantum computation can equally be formulated for pseudo-Hermitian systems. Starting from a deg...


[Phys. Rev. A 100, 042316] Published Wed Oct 16, 2019

Categories: Journals, Physics

Enabling entanglement distillation via optomechanics

Mon, 2019-10-14 12:00

Author(s): Victor Montenegro, Alessandro Ferraro, and Sougato Bose

Quantum networking based on optical Gaussian states, although promising in terms of scalability, is hindered by the fact that their entanglement cannot be distilled via Gaussian operations. We show that optomechanics, and particularly the possibility to measure the mechanical degree of freedom in an...


[Phys. Rev. A 100, 042310] Published Mon Oct 14, 2019

Categories: Journals, Physics

Nonlocal quantum correlations under amplitude damping decoherence

Mon, 2019-10-14 12:00

Author(s): Tanumoy Pramanik, Young-Wook Cho, Sang-Wook Han, Sang-Yun Lee, Sung Moon, and Yong-Su Kim

Different nonlocal quantum correlations of entanglement, steering and Bell nonlocality are defined with the help of local hidden state and local hidden variable models. Considering their unique roles in quantum information processing, it is of importance to understand the individual nonlocal quantum...


[Phys. Rev. A 100, 042311] Published Mon Oct 14, 2019

Categories: Journals, Physics

Erasure decoding of two-dimensional color codes

Mon, 2019-10-14 12:00

Author(s): Arun B. Aloshious and Pradeep Kiran Sarvepalli

The quantum erasure channel models phenomena such as loss or leakage of qubits. Using quantum codes, we can recover from such errors. In this paper, we are interested in studying the performance of two-dimensional color codes over the quantum erasure channel. Our approach makes use of the local equi...


[Phys. Rev. A 100, 042312] Published Mon Oct 14, 2019

Categories: Journals, Physics

Experimental 4-intensity decoy-state quantum key distribution with asymmetric basis-detector efficiency

Mon, 2019-10-14 12:00

Author(s): Hui Liu, Zong-Wen Yu, Mi Zou, Yan-Lin Tang, Yong Zhao, Jun Zhang, Xiang-Bin Wang, Teng-Yun Chen, and Jian-Wei Pan

The decoy-state method has been developed rapidly in quantum key distribution (QKD) since it is immune to photon-number splitting attacks. We examine two-basis-detector-efficiency asymmetry, which exists in realistic scenarios. By using the recent 4-intensity decoy-state optimization protocol, we re...


[Phys. Rev. A 100, 042313] Published Mon Oct 14, 2019

Categories: Journals, Physics

Distributed sampling, quantum communication witnesses, and measurement incompatibility

Mon, 2019-10-14 12:00

Author(s): Leonardo Guerini, Marco Túlio Quintino, and Leandro Aolita

We study prepare-and-measure experiments where the sender (Alice) receives trusted quantum inputs but has an untrusted state-preparation device and the receiver (Bob) has a fully untrusted measurement device. A distributed-sampling task naturally arises in this scenario, where the goal is for Alice ...


[Phys. Rev. A 100, 042308] Published Mon Oct 14, 2019

Categories: Journals, Physics

Quantum entanglement driven by electron-vibrational mode coupling

Mon, 2019-10-14 12:00

Author(s): F. M. Souza, P. A. Oliveira, and L. Sanz

In this work, we show how electron-vibrational mode coupling can be used to drive maximally entangled states. The physical system consists of two pairs of quantum dots, each pair with a single electron able to tunnel between the dots, thus encoding a qubit. The electron-vibrational mode coupling, de...


[Phys. Rev. A 100, 042309] Published Mon Oct 14, 2019

Categories: Journals, Physics

Quantifying superpositions of quantum evolutions

Wed, 2019-10-09 12:00

Author(s): Manabendra N. Bera

Quantum mechanics allows coherent superposition of different states of matter. This quality is responsible for major nonclassical phenomena that occur in quantum systems. Beyond states, coherent superpositions are also possible among quantum evolutions. We characterize such superpositions here. A re...


[Phys. Rev. A 100, 042307] Published Wed Oct 09, 2019

Categories: Journals, Physics

One-shot quantum state exchange

Tue, 2019-10-08 12:00

Author(s): Yonghae Lee, Hayata Yamasaki, Gerardo Adesso, and Soojoon Lee

Quantum state exchange is a quantum communication task in which two users exchange their respective quantum information in the asymptotic setting. In this paper, we consider a one-shot version of the quantum state exchange task, in which the users hold a single copy of the initial state, and they ex...


[Phys. Rev. A 100, 042306] Published Tue Oct 08, 2019

Categories: Journals, Physics

Robust controllability of two-qubit Hamiltonian dynamics

Tue, 2019-10-08 12:00

Author(s): Ryosuke Sakai, Akihito Soeda, Mio Murao, and Daniel Burgarth

Physically, quantum gates (unitary gates) for quantum computation are implemented by controlling the Hamiltonian dynamics of quantum systems. When full descriptions of the Hamiltonians are given, the set of implementable quantum gates is easily characterized by quantum control theory. In many real s...


[Phys. Rev. A 100, 042305] Published Tue Oct 08, 2019

Categories: Journals, Physics