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Related papers: Optimal control theory for unitary transformations

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Optimal control theory is a powerful tool for improving figures of merit in quantum information tasks. Finding the solution to any optimal control problem via numerical optimization depends crucially on the choice of the optimization…

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…

The optimal quantum control theory is employed to determine electric pulses capable of producing quantum gates with high fidelity (higher than 0.9997). Particularly, these quantum gates were chosen to perform the permutation algorithm (Z.…

Quantum Physics · Physics 2018-03-28 C. M. Rivera-Ruiz , E. F. de Lima , F. F. Fanchini , V. Lopez-Richard , L. K. Castelano

We apply quantum optimal control theory (QOCT) to an exactly solvable non-Markovian open quantum bit (qubit) system to achieve state-independent quantum control and construct high-fidelity quantum gates for moderate qubit decaying…

Quantum Physics · Physics 2014-06-12 Jung-Shen Tai , Kuan-Ting Lin , Hsi-Sheng Goan

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

We consider a unitary transformation which maps any given state of an $n$-qubit quantum register into another one. This transformation has applications in the initialization of a quantum computer, and also in some quantum algorithms.…

Quantum Physics · Physics 2007-05-23 Mikko Mottonen , Juha J. Vartiainen , Ville Bergholm , Martti M. Salomaa

Quantum control in large dimensional Hilbert spaces is essential for realizing the power of quantum information processing. For closed quantum systems the relevant input/output maps are unitary transformations, and the fundamental challenge…

Quantum Physics · Physics 2014-10-17 B. E. Anderson , H. Sosa-Martinez , C. A. Riofrío , I. H. Deutsch , P. S. Jessen

Optimal control theory is developed for the task of obtaining a primary objective in a subspace of the Hilbert space while avoiding other subspaces of the Hilbert space. The primary objective can be a state-to-state transition or a unitary…

Quantum Physics · Physics 2008-06-13 Jose P. Palao , Ronnie Kosloff , Christiane P. Koch

Quantum control refers to our ability to manipulate quantum systems. This tutorial-style chapter focuses on the use of classical electromagnetic fields to steer the system dynamics. In this approach, the quantum nature of the control stems…

Quantum Physics · Physics 2025-12-05 Christiane P. Koch

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…

The control of flying qubits carried by itinerant photons is ubiquitous in quantum networks. Beside their logical states, the shape of flying qubits must also be tailored for high-efficiency information transmission. In this paper, we…

Quantum Physics · Physics 2025-11-11 Xue Dong , Xi Cao , Wen-Long Li , Guofeng Zhang , Zhihui Peng , Re-Bing Wu

Quantum technologies will ultimately require manipulating many-body quantum systems with high precision. Cold atom experiments represent a stepping stone in that direction: a high degree of control has been achieved on systems of increasing…

Quantum optimal control is a set of methods for designing time-varying electromagnetic fields to perform operations in quantum technologies. This tutorial paper introduces the basic elements of this theory based on the Pontryagin maximum…

Quantum Physics · Physics 2024-06-17 Q. Ansel , E. Dionis , F. Arrouas , B. Peaudecerf , S. Guérin , D. Guéry-Odelin , D. Sugny

Quantum control allows us to address the problem of engineering quantum dynamics for special purposes. While recently the field of quantum batteries has attracted much attention, optimization of their charging has not benefited from the…

Quantum Physics · Physics 2024-04-12 R. R. Rodriguez , B. Ahmadi , G. Suarez , P. Mazurek , S. Barzanjeh , P. Horodecki

The angular momentum of molecules, or, equivalently, their rotation in three-dimensional space, is ideally suited for quantum control. Molecular angular momentum is naturally quantized, time evolution is governed by a well-known Hamiltonian…

Quantum Physics · Physics 2019-10-23 Christiane P. Koch , Mikhail Lemeshko , Dominique Sugny

Optimal control theory provides recipes to achieve quantum operations with high fidelity and speed, as required in quantum technologies such as quantum sensing and computation. While technical advances have achieved the ultrastrong driving…

Quantum Physics · Physics 2015-11-25 M. Hirose , P. Cappellaro

Constructing high-fidelity control fields that are robust to control, system, and/or surrounding environment uncertainties is a crucial objective for quantum information processing. Using the two-state Landau-Zener model for illustrative…

Quantum Physics · Physics 2012-05-23 Matthew D. Grace , Jason Dominy , Wayne M. Witzel , Malcolm S. Carroll

Closed bipartite quantum systems subject to fast local unitary control are studied using quantum optimal control theory and a method of reduced control systems based on the Schmidt decomposition. Particular focus is given to the…

Quantum Physics · Physics 2024-05-31 Emanuel Malvetti , Léo Van Damme

Quantum optimal control is a technique for controlling the evolution of a quantum system and has been applied to a wide range of problems in quantum physics. We study a binary quantum control optimization problem, where control decisions…

Quantum Physics · Physics 2024-10-15 Xinyu Fei , Lucas T. Brady , Jeffrey Larson , Sven Leyffer , Siqian Shen

Quantum computing can provide speedups in solving many problems as the evolution of a quantum system is described by a unitary operator in an exponentially large Hilbert space. Such unitary operators change the phase of their eigenstates…

Quantum Physics · Physics 2024-01-23 Youle Wang , Lei Zhang , Zhan Yu , Xin Wang