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Related papers: Evolution equation for quantum coherence

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We investigate the long-lived quantum coherence of two-level spontaneous emission models within structured environments. The population of the system under the asymptotic non-Markovian dynamics is linked to the spectral density of the…

Quantum Physics · Physics 2018-06-19 Ping Zhang , Bo You , Li-Xiang Cen

Quantum channels describe subsystem or open system evolution. Using the classical Koopman operator that evolves functions on phase space, 4 classical Koopman channels are identified that are analogs of the 4 possible quantum channels in a…

Quantum Physics · Physics 2024-07-22 Bidhi Vijaywargia , Arul Lakshminarayan

Phase covariant qubit dynamics describes an evolution of a two-level system under simultaneous action of pure dephasing, energy dissipation, and energy gain with time-dependent rates $\gamma_z(t)$, $\gamma_-(t)$, and $\gamma_+(t)$,…

Quantum Physics · Physics 2020-04-24 S. N. Filippov , A. N. Glinov , L. Leppäjärvi

We address measurement-based generation of quantum coherence in continuous variable systems. We consider Gaussian measurements performed on Gaussian states and focus on two scenarios. In the first one, we assume an initially correlated…

Quantum Physics · Physics 2017-08-14 Francesco Albarelli , Marco G. Genoni , Matteo G. A. Paris

Quantum resource theories provide a diverse and powerful framework for extensively studying the phenomena in quantum physics. Quantum coherence, a quantum resource, is the basic ingredient in many quantum information tasks. It is a subject…

Quantum Physics · Physics 2021-05-19 Sunho Kim , Chunhe Xiong , Asutosh Kumar , Junde Wu

Coherence and correlation are key features of the quantum system. Quantifying these quantities are astounding task in the framework of resource theory of quantum information processing. In this article, we identify an affinity-based metric…

Quantum Physics · Physics 2021-02-11 R. Muthuganesan , V. K. Chandrasekar , R. Sankaranarayanan

Entanglement and coherence are fundamental properties of quantum systems, promising to power near future quantum technologies, such as quantum computation, quantum communication and quantum metrology. Yet, their quantification, rather than…

Coupled quantum dots are an example of the ubiquitous quantum double potential well. In a typical transport experiment, each quantum dot is also coupled to a continuum of states. Our approach takes this into account by using a Green's…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 D. M. Cardamone , C. A. Stafford , B. R. Barrett

The ability of quantum states to be in superposition is one of the key features that sets them apart from the classical world. This `coherence' is rigorously quantified by resource theories, which aim to understand how such properties may…

Quantum Physics · Physics 2024-07-08 Ruvi Lecamwasam , Syed M Assad , Joseph J Hope , Ping Koy Lam , Jayne Thompson , Mile Gu

We study the stability of entanglement in a quantum computer implementing an efficient quantum algorithm, which simulates a quantum chaotic dynamics. For this purpose, we perform a forward-backward evolution of an initial state in which two…

Quantum Physics · Physics 2007-05-23 Davide Rossini , Giuliano Benenti , Giulio Casati

We introduce measures of quantum coherence as the speed of evolution of a system under decoherence. That is, coherence is the ability to estimate a dephasing channel, quantified by the quantum Fisher information. We extend the analysis to…

Quantum Physics · Physics 2019-01-23 Benjamin Yadin , Pieter Bogaert , Cristian E. Susa , Davide Girolami

Quantum coherence constitutes a foundational characteristic of quantum mechanics and is integral to emerging quantum resource theories. However, quantum coherence is severely restricted by environmental noise in general quantum processing,…

Quantum Physics · Physics 2024-05-24 Qing-Hua Zhang , Shao-Ming Fei

We discuss the role of quantum coherence in the energy fluctuations of open quantum systems. To this aim, we introduce a protocol, to which we refer to as the end-point-measurement scheme, allowing to define the statistics of energy changes…

Quantum Physics · Physics 2022-04-13 S. Gherardini , A. Belenchia , M. Paternostro , A. Trombettoni

Coherent states consist of superposition of infinite number of particles and do not have a classical analogue. We study their evolution in a FLRW cosmology and show that only when full quantum corrections are considered, they may survive…

High Energy Physics - Phenomenology · Physics 2015-08-26 Houri Ziaeepour

We study dynamics of quantum entanglement in smooth global quenches with a finite rate, by computing the time evolution of entanglement entropy in 1 + 1 dimensional free scalar theory with time-dependent masses which start from a nonzero…

High Energy Physics - Theory · Physics 2018-01-15 Mitsuhiro Nishida , Masahiro Nozaki , Yuji Sugimoto , Akio Tomiya

Quantum coherence is a key element in topical research on quantum resource theories and a primary facilitator for design and implementation of quantum technologies. However, the resourcefulness of quantum coherence is severely restricted by…

Quantum Physics · Physics 2015-06-01 Uttam Singh , Manabendra Nath Bera , Himadri Shekhar Dhar , Arun Kumar Pati

In the present work we recall and extend the results of previous work concerning the time evolution of open quantum systems. We show how general properties of such systems are related to their structure properties, those of their…

Quantum Physics · Physics 2016-06-01 Tarek Khalil , Jean Richert

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

Entanglement plays a crucial role in quantum processes particularly those pertaining to quantum information and computation. An analytical expression for an entanglement measure defined in terms of success rate of Grover's search algorithm…

Quantum Physics · Physics 2007-05-23 Arti Chamoli , C. M. Bhandari

The coherent evolution of two atomic qubits mediated by a set of bosonic field modes is investigated. By assuming a specific encoding of the quantum states in the internal levels of the two atoms we show that entangling quantum gates can be…

Quantum Physics · Physics 2015-05-18 Sai-Yun Ye , Zhen-Biao Yang , Shi-Biao Zheng , Alessio Serafini