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Many quantum control problems are formulated as a search for an optimal field that maximizes a physical objective. This search is performed over a landscape defined as the objective as a function of the control field. A recent Letter [A. N.…

Quantum Physics · Physics 2012-05-09 Herschel Rabitz , Tak-San Ho , Ruixing Long , Rebing Wu , Constantin Brif

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

There is a strong interest in optimal manipulating of quantum systems by external controls. Traps are controls which are optimal only locally but not globally. If they exist, they can be serious obstacles to the search of globally optimal…

Quantum Physics · Physics 2015-09-03 Alexander Pechen , Nikolay Il'in

Quantum optimal control has enjoyed wide success for a variety of theoretical and experimental objectives. These favorable results have been attributed to advantageous properties of the corresponding control landscapes, which are free from…

Advancing quantum technologies requires precise and robust coherent control of quantum systems. Robust higher-order Hamiltonian engineering is essential for high-precision control and for accessing effective dynamics absent at zeroth order.…

Quantum Physics · Physics 2026-03-13 Jiahui Chen , David Cory

The success of quantum optimal control for both experimental and theoretical objectives is connected to the topology of the corresponding control landscapes, which are free from local traps if three conditions are met: (1) the quantum…

$\Lambda$, $V$, $\Xi$ (ladder), and other three-level quantum systems with one forbidden transition ($\Lambda$-type systems) play an important role in quantum physics. Various applications require manipulation by such systems using as…

Quantum Physics · Physics 2025-02-25 Boris Volkov , Anastasia Myachkova , Alexander Pechen

Optimal quantum control of continuous variable systems poses a formidable computational challenge because of the high-dimensional character of the system dynamics. The framework of quantum invariants can significantly reduce the complexity…

Robust control of quantum systems is an increasingly relevant field of study amidst the second quantum revolution, but there remains a gap between taming quantum physics and robust control in its modern analytical form that culminated in…

Although quantum control typically relies on greedy (local) optimization, traps (irregular critical points) in the control landscape can make optimization hard by foiling local search strategies. We demonstrate the failure of greedy…

Quantum Physics · Physics 2014-09-17 Ehsan Zahedinejad , Sophie Schirmer , Barry C. Sanders

The problems of optimizing the value of an arbitrary observable of the two-level system at both a fixed time and the shortest possible time is theoretically explored. Complete identification and classification along with comprehensive…

Quantum Physics · Physics 2016-12-02 Dmitry V. Zhdanov , Tamar Seideman

In this dissertation I analyze Hamiltonian control of $d$-dimensional quantum systems as realized in alkali atomic spins. Alkali atoms provide an ideal platform for studies of quantum control due to the extreme precision with which the…

Quantum Physics · Physics 2009-06-29 Seth Merkel

We describe algorithms, and experimental strategies, for the Pareto optimal control problem of simultaneously driving an arbitrary number of quantum observable expectation values to their respective extrema. Conventional quantum optimal…

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

Fast control of quantum systems is essential in order to make use of quantum properties before they are degraded by decoherence. This is important for quantum-enhanced information processing, as well as for pushing quantum systems into…

Quantum Physics · Physics 2016-04-12 J. Alonso , F. M. Leupold , Z. U. Soler , M. Fadel , M. Marinelli , B. C. Keitch , V. Negnevitsky , J. P. Home

We present setups for the practical realization of adding control to unknown subroutines, supplementing the existing quantum optical scheme for black-box control with a counterpart for the quantum control of the ordering of sequences of…

Quantum Physics · Physics 2014-03-14 Nicolai Friis , Vedran Dunjko , Wolfgang Dür , Hans J. Briegel

Classical simulations of time-dependent quantum systems are widely used in quantum control research. In particular, these simulations are commonly used to host iterative optimal control algorithms. This is convenient for algorithms that are…

Quantum Physics · Physics 2021-11-23 Tyler Jones , Kaiah Steven , Xavier Poncini , Matthew Rose , Arkady Fedorov

The control landscape for various canonical quantum control problems is considered. For the class of pure-state transfer problems, analysis of the fidelity as a functional over the unitary group reveals no suboptimal attractive critical…

Quantum Physics · Physics 2014-03-04 Pierre de Fouquieres , Sophie G. Schirmer

A quantum control landscape is defined as the objective to be optimized as a function of the control variables. Existing empirical and theoretical studies reveal that most realistic quantum control landscapes are generally devoid of false…

Quantum Physics · Physics 2013-04-01 Rebing Wu , Jason Dominy , Tak-San Ho , Herschel Rabitz

We study the application of a generalized form of the level set method used in classical physical contexts to quantum optimal control situations. The set of OCT equations needed to keep the expectation value of an observable constant is…

Quantum Physics · Physics 2007-05-23 Fariel Shafee

Trapped ion hardware has made significant progress recently and is now one of the leading platforms for quantum computing. To construct two-qubit gates in trapped ions, experimental manipulation approaches for ion chains are becoming…

Quantum Physics · Physics 2022-11-16 Jing-Bo Wang
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