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Related papers: Quantum Control Landscapes: A Closer Look

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This review investigates the landscapes of prevalent hybrid quantum-classical optimization algorithms in many rapidly developing quantum technologies, where the objective function is either computed by a natural quantum system or a quantum…

Quantum Physics · Physics 2022-04-12 Xiaozhen Ge , Re-Bing Wu , Herschel Rabitz

Optimal control of closed quantum systems is a well studied geometrically elegant set of computational theory and techniques that have proven pivotal in the implementation and understanding of quantum computers. The design of a circuit…

Quantum Physics · Physics 2024-04-29 Johannes Aspman , Vyacheslav Kungurtsev , Jakub Marecek

Quantum control is valuable for various quantum technologies such as high-fidelity gates for universal quantum computing, adaptive quantum-enhanced metrology, and ultra-cold atom manipulation. Although supervised machine learning and…

Machine Learning · Computer Science 2017-09-06 Pantita Palittapongarnpim , Peter Wittek , Ehsan Zahedinejad , Shakib Vedaie , Barry C. Sanders

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

An approach is presented for robustness analysis and quantum (unitary) control synthesis based on the classic method of averaging. The result is a multicriterion optimization competing the nominal (uncertainty-free) fidelity with a well…

Quantum Physics · Physics 2022-08-31 Robert L. Kosut , Gaurav Bhole , 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

A linear control system with quadratic cost functional over infinite time horizon is considered without assuming controllability/stabilizability condition and the global integrability condition for the nonhomogeneous term of the state…

Optimization and Control · Mathematics 2020-08-25 Jianping Huang , Jiongmin Yong , Hua-Cheng Zhou

We show that optimizing a quantum gate for an open quantum system requires the time evolution of only three states irrespective of the dimension of Hilbert space. This represents a significant reduction in computational resources compared…

Quantum Physics · Physics 2021-02-16 Michael H. Goerz , Daniel M. Reich , Christiane P. Koch

In optimal quantum control, control landscape phase transitions (CLPTs) indicate sharp changes occurring in the set of optimal protocols, as a physical model parameter is varied. Here, we demonstrate the existence of a new class of CLPTs,…

Quantum Physics · Physics 2025-11-03 Nicolò Beato , Pranay Patil , Marin Bukov

Optically linked ion traps are promising as components of network-based quantum technologies, including communication systems and modular computers. Experimental results achieved to date indicate that the fidelity of operations within each…

Quantum Physics · Physics 2016-10-25 Ramil Nigmatullin , Christopher J. Ballance , Niel de Beaudrap , Simon C. Benjamin

In the design of complex quantum systems like ion traps for quantum computing, it is usually desired to stabilize a particular system state or make the system state track a desired trajectory. Several control theoretical approaches based on…

Systems and Control · Computer Science 2012-11-26 K. P. Nagarjun , S. Sivaranjani , George Koshy

This paper revisits the classical Linear Quadratic Gaussian (LQG) control from a modern optimization perspective. We analyze two aspects of the optimization landscape of the LQG problem: 1) connectivity of the set of stabilizing controllers…

Optimization and Control · Mathematics 2021-02-09 Yang Zheng , Yujie Tang , Na Li

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

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

In quantum optimal control theory the success of an optimization algorithm is highly influenced by how the figure of merit to be optimized behaves as a function of the control field, i.e. by the control landscape. Constraints on the control…

Quantum Physics · Physics 2016-04-07 Niklas Rach , Matthias M. Müller , Tommaso Calarco , Simone Montangero

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

We establish three tractable, jointly sufficient conditions for the control landscapes of non-linear control systems to be trap free comparable to those now well known in quantum control. In particular, our results encompass end-point…

Optimization and Control · Mathematics 2018-08-01 Benjamin Russell , Shanon Vuglar , Herschel Rabitz

We present deterministic algorithms for the simultaneous control of an arbitrary number of quantum observables. Unlike optimal control approaches based on cost function optimization, quantum multiobservable tracking control (MOTC) is…

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

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

In this work, we address the problem of maximizing fidelity in a quantum state transformation process controlled in such a way as to keep decoherence within given bounds. We consider a three-level $\Lambda$-type atom subjected to Markovian…

Quantum Physics · Physics 2022-03-30 Nahid Binandeh Dehaghani , Fernando Lobo Pereira