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A chaos control algorithm is developed to actively stabilize unstable periodic orbits of higher-dimensional systems. The method assumes knowledge of the model equations and a small number of experimentally accessible parameters. General…

chao-dyn · Physics 2019-08-17 A. Pentek , J. B. Kadtke , Z. Toroczkai

A major obstacle in the way of practical quantum computing is achieving scalable and robust high-fidelity entangling gates. To this end, quantum control has become an essential tool, as it can make the entangling interaction resilient to…

Quantum Physics · Physics 2022-10-05 Christophe H. Valahu , Iason Apostolatos , Sebastian Weidt , Winfried K. Hensinger

A proof that almost all quantum systems have trap free (that is, free from local optima) landscapes is presented for a large and physically general class of quantum system. This result offers an explanation for why gradient methods succeed…

Quantum Physics · Physics 2016-11-14 Benjamin Russell , Herschel Rabitz , Rebing Wu

The paper examines the prominent algorithm D-MORPH to search for the optimal control of a quantum system in order to implement desired unitary evolution of the quantum system at the final time, and reveals new mathematical expressions for…

Quantum Physics · Physics 2017-09-19 Konstantin Zhdanov

We introduce a novel algorithm for the task of coherently controlling a quantum mechanical system to implement any chosen unitary dynamics. It performs faster than existing state of the art methods by one to three orders of magnitude…

Quantum Physics · Physics 2015-06-04 Pierre de Fouquieres

We investigate the control landscapes of closed, finite level quantum systems beyond the dipole approximation by including a polarizability term in the Hamiltonian. Theoretical analysis is presented for the $n$ level case and formulas for…

Quantum Physics · Physics 2016-02-22 Benjamin Russell , Herschel Rabitz , Rebing Wu

This thesis addresses the problem of developing a quantum counter-part of the well established classical theory of control. We dwell on the fundamental fact that quantum states are generally not perfectly distinguishable, and quantum…

Quantum Physics · Physics 2009-08-21 Paulo E. M. F. Mendonca

Control of quantum operations is a crucial yet expensive construct for quantum computation. Efficient implementations of controlled operations often avoid applying control to certain subcircuits, which can significantly reduce the number of…

Quantum Physics · Physics 2025-05-27 Peleg Emanuel , Eyal Cornfeld , Ravid Alon , Shmuel Ur , Israel Reichental

Numerous lines of experimental, numerical and analytical evidence indicate that it is surprisingly easy to locate optimal controls steering quantum dynamical systems to desired objectives. This has enabled the control of complex quantum…

Quantum Physics · Physics 2015-05-13 Raj Chakrabarti , Herschel Rabitz

Simultaneous optimization of multiple quantum objectives is often considered a demanding task. However, a special circumstance arises when a primary objective is pitted against a set of secondary objectives, which we show leads to invariant…

Quantum Physics · Physics 2015-07-22 David Hocker , Herschel Rabitz

Quantum Optimal Control is an established field of research which is necessary for the development of Quantum Technologies. In recent years, Machine Learning techniques have been proved usefull to tackle a variety of quantum problems. In…

An operational description of quantum phenomena concerns developing models that describe experimentally observed behaviour. $\textit{Higher-order quantum operations}\unicode{x2014}$quantum operations that transform quantum…

Quantum Physics · Physics 2025-03-14 Philip Taranto , Simon Milz , Mio Murao , Marco Túlio Quintino , Kavan Modi

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

This paper discusses the important role of controllability played on the complexity of optimizing quantum mechanical control systems. The study is based on a topology analysis of the corresponding quantum control landscape, which is…

Quantum Physics · Physics 2013-04-01 Re-Bing Wu , Michael A. Hsieh , Herschel Rabitz

The analysis of traps, i.e., locally but not globally optimal controls, for quantum control systems has attracted a great interest in recent years. The central problem that has been remained open is to demonstrate for a given system either…

Quantum Physics · Physics 2013-04-05 Alexander Pechen , Nikolay Il'in

Control of quantum systems is a central element of high-precision experiments and the development of quantum technological applications. Control pulses that are typically temporally or spatially modulated are often designed based on…

Quantum Physics · Physics 2021-01-04 Frederic Sauvage , Florian Mintert

Dynamical decoupling represents an active approach towards the protection of quantum memories and quantum gates. Because dynamical decoupling operations can interfere with a system's own time evolution, the protection of quantum gates is…

Quantum Physics · Physics 2025-02-25 P. Z. Zhao , Tianqi Chen , Sirui Liu , Jiangbin Gong

Quantum control for error correction is critical for the practical use of quantum computers. We address quantum optimal control for single-shot multi-qubit gates by framing as a feasibility problem for the Hamiltonian model and then solving…

Quantum Physics · Physics 2019-05-07 Raymond J. Spiteri , Marina Schmidt , Joydip Ghosh , Ehsan Zahedinejad , Barry C. Sanders

Higher-order quantum theory is an extension of quantum theory where one introduces transformations whose input and output are transformations, thus generalizing the notion of channels and quantum operations. The generalization then goes…

Quantum Physics · Physics 2019-05-28 Alessandro Bisio , Paolo Perinotti

Toward scalable quantum computing, the control of quantum systems needs to be robust against both coherent errors induced by parametric uncertainties and incoherent errors induced by environmental decoherence. This poses significant…

Quantum Physics · Physics 2025-07-11 Yidian Fan , Re-Bing Wu