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Related papers: Quantum brachistochrone curves as geodesics: obtai…

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We present a time-parallelization method that enables to accelerate the computation of quantum optimal control algorithms. We show that this approach is approximately fully efficient when based on a gradient method as optimization solver:…

Optimization and Control · Mathematics 2016-05-04 Mohamed-Kamel Riahi , Julien Salomon , S. J. Glaser , D Sugny

We present a general theoretical framework for finding the time-optimal unitary evolution of the quantum systems when the Hamiltonian is subject to arbitrary constraints. Quantum brachistochrone (QB) is such a framework based on the…

Quantum Physics · Physics 2020-07-21 Hiroaki Wakamura , Tatsuhiko Koike

We investigate the optimization of quantum control from a differential geometric perspective. In our approach, optimal control minimizes the cost associated with evolving a quantum state, with the cost quantified by the length of the…

Quantum Physics · Physics 2025-05-27 Chengming Tan , Yuhao Cai , Jinyi Zhang , Shengli Ma , Chenwei Lv , Ren Zhang

We introduce a strategy to develop optimally designed fields for continuous dynamical decoupling. Using our methodology, we obtain the optimal continuous field configuration to maximize the fidelity of a general one-qubit quantum gate. To…

This paper shows that the well-known curve optimization problems which lead to the straight line, the catenary curve, the brachistochrone, and the circle, can all be handled using a unified formalism. Furthermore, from the general…

History and Overview · Mathematics 2014-01-14 Raul Rojas

We revisit the issue of time in quantum geometrodynamics and suggest a quantization procedure on the space of true dynamic variables. This procedure separates the issue of quantization from enforcing the constraints caused by the general…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Warner A. Miller , Arkady Kheyfets

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

Universal robust quantum control is essential for performing complex quantum algorithms and efficient quantum error correction protocols. Geometric phase, as a key element with intrinsic fault-tolerant feature, can be well integrated into…

Quantum Physics · Physics 2024-12-17 Tao Chen , Jia-Qi Hu , Chengxian Zhang , Zheng-Yuan Xue

In many problems in optimal control, one seeks to minimise an objective function subject to constraints on the velocity of the system. Imposing these constraints directly -- the ``hard-constrained'' approach -- is often analytically and…

Optimization and Control · Mathematics 2026-04-27 Rufus Lawrence , Aleš Wodecki , Johannes Aspman , Jakub Mareček

Determining the quantum circuit complexity of a unitary operation is closely related to the problem of finding minimal length paths in a particular curved geometry [Nielsen et al, Science 311, 1133-1135 (2006)]. This paper investigates many…

Quantum Physics · Physics 2007-05-23 Mark R. Dowling , Michael A. Nielsen

Optimization of constrained quantum control problems powers quantum technologies. This task becomes very difficult when these control problems are nonconvex and plagued with dense local extrema. For such problems current optimization…

Dynamically correcting for unwanted interactions between a quantum system and its environment is vital to achieving the high-fidelity quantum control necessary for a broad range of quantum information technologies. In recent work, we…

Quantum Physics · Physics 2018-07-11 Junkai Zeng , Edwin Barnes

Hybrid quantum-classical algorithms hold great promise for solving quantum control problems on near-term quantum computers. In this work, we employ the hybrid framework that integrates digital quantum simulation with classical optimization…

Quantum Physics · Physics 2025-07-01 Tangyou Huang , Jing-Jun Zhu , Zhong-Yi Ni

A longstanding problem in quantum metrology is how to extract as much information as possible in realistic scenarios with not only multiple unknown parameters, but also limited measurement data and some degree of prior information. Here we…

Quantum Physics · Physics 2020-03-24 Jesús Rubio , Jacob Dunningham

In quantum control, geometrical operations could provide an extra layer of robustness against control errors. However, the conventional non-adiabatic holonomic quantum computation (NHQC) is limited by the fact that all of the operations…

Quantum Physics · Physics 2021-03-02 Bao-Jie Liu , Zheng-Yuan Xue , Man-Hong Yung

Optimizing the controls of quantum systems plays a crucial role in advancing quantum technologies. The time-varying noises in quantum systems and the widespread use of inhomogeneous quantum ensembles raise the need for high-quality quantum…

Quantum Physics · Physics 2025-05-06 Xinyu Fei , Lucas T. Brady , Jeffrey Larson , Sven Leyffer , Siqian Shen

Recently, Bender et al. have considered the quantum brachistochrone problem for the non-Hermitian $\cal PT$-symmetric quantum system and have shown that the optimal time evolution required to transform a given initial state $|\psi_i\rangle$…

Quantum Physics · Physics 2009-07-07 Alexander I. Nesterov

Quantum computing has garnered attention for its potential to solve complex computational problems with considerable speedup. Despite notable advancements in the field, achieving meaningful scalability and noise control in quantum hardware…

Quantum Physics · Physics 2025-05-12 Eduardo Willwock Lussi , Rafael de Santiago , Eduardo Inacio Duzzioni

We propose a method to obtain optimal protocols for adiabatic ground-state preparation near the adiabatic limit, extending earlier ideas from [D. A. Sivak and G. E. Crooks, Phys. Rev. Lett. 108, 190602 (2012)] to quantum non-dissipative…

Quantum Gases · Physics 2016-07-20 Michael Tomka , Tiago Souza , Steven Rosenberg , Anatoli Polkovnikov

Recently, the quantum brachistochrone problem is discussed in the literature by using non-Hermitian Hamilton operators of different type. Here, it is demonstrated that the passage time is tunable in realistic open quantum systems due to the…

Quantum Physics · Physics 2009-11-13 Ingrid Rotter