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Related papers: The role of controllability in optimizing quantum …

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Optimization is ubiquitous in quantum information science and technology, however, the corresponding optimization landscape can encounter false traps, i.e., local but not global optima, likely to prevent used optimizers from finding optimal…

Quantum Physics · Physics 2026-03-06 Xiaozhen Ge , Shuming Cheng , Guofeng Zhang , Re-Bing Wu

Optimal control can be used to significantly improve multi-qubit gates in quantum information processing hardware architectures based on superconducting circuit quantum electrodynamics. We apply this approach not only to dispersive gates of…

Quantum Physics · Physics 2015-05-14 R. Fisher , F. Helmer , S. J. Glaser , F. Marquardt , T. Schulte-Herbrueggen

The broad success of optimally controlling quantum systems with external fields has been attributed to the favorable topology of the underlying control landscape, where the landscape is the physical observable as a function of the controls.…

Quantum Physics · Physics 2015-06-03 Katharine W. Moore , Herschel Rabitz

The control of quantum systems has been proven to possess trap-free optimization landscapes under the satisfaction of proper assumptions. However, many details of the landscape geometry and their influence on search efficiency still need to…

Quantum Physics · Physics 2024-09-27 Yidian Fan , Re-Bing Wu , Tak-San Ho , Gaurav V. Bhole , Herschel Rabitz

There has been great interest in recent years in quantum control landscapes. Given an objective $J$ that depends on a control field $\varepsilon$ the dynamical landscape is defined by the properties of the Hessian $\delta^2…

Quantum Physics · Physics 2015-08-25 Alexander N. Pechen , David J. Tannor

Methods of optimal control are applied to a model system of interacting two-level particles (e.g., spin-half atomic nuclei or electrons or two-level atoms) to produce high-fidelity quantum gates while simultaneously negating the detrimental…

We apply the methodology of optimal control theory to the problem of implementing quantum gates in continuous variable systems with quadratic Hamiltonians. We demonstrate that it is possible to define a fidelity measure for continuous…

Quantum Physics · Physics 2009-11-13 Rebing Wu , Raj Chakrabarti , Herschel Rabitz

A quantum control landscape is defined as the expectation value of a target observable $\Theta$ as a function of the control variables. In this work control landscapes for open quantum systems governed by Kraus map evolution are analyzed.…

A quantum system subject to external fields is said to be controllable if these fields can be adjusted to guide the state vector to a desired destination in the state space of the system. Fundamental results on controllability are reviewed…

Nuclear Theory · Physics 2008-11-26 John W. Clark , Dennis G. Lucarelli , Tzyh-Jong Tarn

Control of multi-level quantum systems is sensitive to implementation errors in the control field and uncertainties associated with system Hamiltonian parameters. A small variation in the control field spectrum or the system Hamiltonian can…

Quantum Physics · Physics 2015-06-23 Andy Koswara , Raj Chakrabarti

This work develops measures for quantifying the effects of field noise upon targeted unitary transformations. Robustness to noise is assessed in the framework of the quantum control landscape, which is the mapping from the control to the…

A quantum control landscape is defined as the physical objective as a function of the control variables. In this paper the control landscapes for two-level open quantum systems, whose evolution is described by general completely positive…

Quantum Physics · Physics 2008-01-15 Alexander Pechen , Dmitrii Prokhorenko , Rebing Wu , Herschel Rabitz

We show that the second order traps in the control landscape for a three-level $\Lambda$-system found in our previous work {\it Phys. Rev. Lett.} {\bf 106}, 120402 (2011) are not local maxima: there exist directions in the space of controls…

Quantum Physics · Physics 2015-08-19 Alexander Pechen , David J. Tannor

A common goal in the sciences is optimization of an objective function by selecting control variables such that a desired outcome is achieved. This scenario can be expressed in terms of a control landscape of an objective considered as a…

Quantum Physics · Physics 2017-02-08 Benjamin Russell , Herschel Rabitz

Controlling complex networked systems to a desired state is a key research goal in contemporary science. Despite recent advances in studying the impact of network topology on controllability, a comprehensive understanding of the synergistic…

Optimization and Control · Mathematics 2014-08-04 Chen Zhao , Wen-Xu Wang , Yang-Yu Liu , Jean-Jacques Slotine

The importance of feedback control is being increasingly appreciated in quantum physics and applications. This paper describes the use of optimal control methods in the design of quantum feedback control systems, and in particular the paper…

Quantum Physics · Physics 2009-11-10 M. R. James

Quantum state preparation is vital to quantum computation and quantum information processing tasks. In adiabatic state preparation, the target state is theoretically obtained with nearly perfect fidelity if the control parameter is tuned…

Quantum Gases · Physics 2024-02-12 Xikun Li , Daniel Pęcak , Tomasz Sowiński , Jacob Sherson , Anne E. B. Nielsen

Many phenomena in physics, chemistry, and biology involve seeking an optimal control to maximize an objective for a classical or quantum system which is open and interacting with its environment. The complexity of finding an optimal control…

Quantum Physics · Physics 2010-11-08 Alexander Pechen , Herschel Rabitz

Optimal control theory is a versatile tool that presents a route to significantly improving figures of merit for quantum information tasks. We combine it here with the geometric theory for local equivalence classes of two-qubit operations…

Quantum Physics · Physics 2015-03-19 M. M. Müller , D. M. Reich , M. Murphy , H. Yuan , J. Vala , K. B. Whaley , T. Calarco , C. P. Koch

Optimal control of molecular dynamics is commonly expressed from a quantum mechanical perspective. However, in most contexts the preponderance of molecular dynamics studies utilize classical mechanical models. This paper treats laser-driven…

Chemical Physics · Physics 2015-03-19 Carlee Joe-Wong , Tak-San Ho , Ruixing Long , Herschel Rabitz , Rebing Wu