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Related papers: Quantifying the Unitary Generation of Coherence Fr…

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We consider the physical situations where the resource theories of coherence and thermodynamics play competing roles. In particular, we study the creation of quantum coherence using unitary operations with limited thermodynamic resources.…

Quantum Physics · Physics 2016-06-01 Avijit Misra , Uttam Singh , Samyadeb Bhattacharya , Arun Kumar Pati

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

Given a preferred orthonormal basis $B$ in the Hilbert space of a quantum system we define a measure of the coherence generating power of a unitary operation with respect to $B$. This measure is the average coherence generated by the…

Quantum Physics · Physics 2017-05-10 Paolo Zanardi , Georgios Styliaris , Lorenzo Campos Venuti

Quantum coherence inherently affects the dynamics and the performances of a quantum machine. Coherent control can, at least in principle, enhance the work extraction and boost the velocity of evolution in an open quantum system. Using…

Quantum Physics · Physics 2018-12-10 Vasco Cavina , Andrea Mari , Alberto Carlini , Vittorio Giovannetti

Constraints on work extraction are fundamental to our operational understanding of the thermodynamics of both classical and quantum systems. In the quantum setting, finite-time control operations typically generate coherence in the…

A new method for controlling harmonic generation, in the framework of quantum optimal control theory (QOCT), is developed. The problem is formulated in the frequency domain using a new maximization functional. The relaxation method is used…

Quantum Physics · Physics 2012-08-28 Ido Schaefer

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

Coherent control of self-contained quantum systems offers the possibility to fabricate smallest thermal transistors. The steady coherence created by the delocalization of electronic excited states arouses nonlinear heat transports in…

Quantum Physics · Physics 2018-11-07 Shanhe Su , Yanchao Zhang , Bjarne Andresen , Jincan Chen

The work done when a system at thermal equilibrium is externally driven by a unitary control parameter leads to irreversible entropy production. The entropy produced can be thought of as a combination of coherence generation and a…

Quantum Physics · Physics 2024-12-30 Krishna Shende , Kavita Dorai , Arvind

Coherent control of harmonic generation was studied theoretically. A specific harmonic order was targeted. An optimal control theory was employed to find the driving field where restrictions were imposed on the frequency band. Additional…

Quantum Physics · Physics 2013-01-04 Ido Schaefer , Ronnie Kosloff

Conventional approaches for controlling open quantum systems use coherent control which affects the system's evolution through the Hamiltonian part of the dynamics. Such control, although being extremely efficient for a large variety of…

Quantum Physics · Physics 2009-05-04 Alexander Pechen , Herschel Rabitz

Quantum coherence, the ability of a quantum system to be in a superposition of orthogonal quantum states, is a distinct feature of the quantum mechanics, thus marking a deviation from classical physics. Coherence finds its applications in…

Quantum Physics · Physics 2023-01-18 Najmeh Etehadi Abari , Andrey Rakhubovsky , Radim Filip

We consider finite sized atomic systems with varying number of particles which have dipolar interactions among them and also under the collective driving and dissipative effect of thermal photon environment. Focusing on the simple case of…

Quantum Physics · Physics 2017-09-25 B. Çakmak , A. Manatuly , Ö. E. Müstecaplıoğlu

The article considers a two-level open quantum system whose dynamics is driven by a combination of coherent and incoherent controls. Coherent control enters into the Hamiltonian part of the dynamics whereas incoherent control enters into…

Quantum Physics · Physics 2019-09-24 Oleg V. Morzhin , Alexander N. Pechen

We study the ability of a quantum channel to generate quantum coherence when it applies to incoherent states. Based on probabilistic averages, we define a measure of such coherence generating power (CGP) for a generic quantum channel, based…

Quantum Physics · Physics 2018-06-14 Lin Zhang , Zhihao Ma , Zhihua Chen , Shao-Ming Fei

The reliable and precise generation of quantum unitary transformations is essential to the realization of a number of fundamental objectives, such as quantum control and quantum information processing. Prior work has explored the optimal…

Quantum Physics · Physics 2010-07-21 Michael Hsieh , Rebing Wu , Herschel Rabitz , Daniel Lidar

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

Errors in the control of quantum systems may be classified as unitary, decoherent and incoherent. Unitary errors are systematic, and result in a density matrix that differs from the desired one by a unitary operation. Decoherent errors…

We establish an operational theory of coherence (or of superposition) in quantum systems, by focusing on the optimal rate of performance of certain tasks. Namely, we introduce the two basic concepts - "coherence distillation" and "coherence…

Quantum Physics · Physics 2016-03-25 Andreas Winter , Dong Yang

This study is focused on the quantum dynamics of a nitrogen-vacancy (NV) center coupled to a nonlinear, periodically driven mechanical oscillator. For a continuous periodic driving that depends on the position of the oscillator, the…

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