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We study optimal control strategies to optimize the relaxation rate towards the fixed point of a quantum system in the presence of a non-Markovian dissipative bath. Contrary to naive expectations that suggest that memory effects might be…

We consider the problem of time optimal control of a continuous bosonic quantum system subject to the action of a Markovian dissipation. In particular, we consider the case of a one mode Gaussian quantum system prepared in an arbitrary…

Quantum Physics · Physics 2014-12-01 Alberto Carlini , Andrea Mari , Vittorio Giovannetti

The relaxation of a system to a steady state is a central point of interest in many attempts to advance control over the quantum world. In this paper, we consider control through instantaneous Gaussian unitary operations on the ubiquitous…

We address the problem of cooling a Markovian quantum system to a pure state in the shortest amount of time possible. Here the system drift takes the form of a Lindblad master equation and we assume fast unitary control. This setting allows…

Quantum Physics · Physics 2024-03-11 Emanuel Malvetti

A formalism based on Pontryagin's maximum principle is applied to determine the time-optimal protocol that drives a general initial state to a target state by a Hamiltonian with limited control, i.e., there is a single control field with…

Quantum Physics · Physics 2020-02-19 Chungwei Lin , Dries Sels , Yebin Wang

We present a theoretical study of the optimal control of a qubit interacting with a structured environment. We consider a model system in which the bath is a bosonic reservoir at zero temperature and the qubit frequency is the only control…

Quantum Physics · Physics 2022-10-04 Quentin Ansel , Jonas Fischer , Dominique Sugny , Bruno Bellomo

We study the problem of optimal control of dissipative quantum dynamics. Although under most circumstances dissipation leads to an increase in entropy (or a decrease in purity) of the system, there is an important class of problems for…

Quantum Physics · Physics 2009-11-10 Shlomo E. Sklarz , David J. Tannor , Navin Khaneja

Optimal control is a central problem in quantum thermodynamics. When minimizing dissipated work and work fluctuations defined via the two-point measurement scheme in open quantum systems, existing approaches largely focus on the rapid- and…

Quantum Physics · Physics 2026-04-08 Yuki Kurokawa , Yoshihiko Hasegawa

We consider the problem of finding the energy minimum of a complex quantum Hamiltonian by employing a non-Markovian bath prepared in a low energy state. The energy minimization problem is thus turned into a thermodynamic cooling protocol in…

Quantum Physics · Physics 2024-03-29 Alberto Imparato , Nicholas Chancellor , Gabriele De Chiara

In this article we explore a modification in the problem of controlling the rotation of a two level quantum system from an initial state to a final state in minimum time. Specifically we consider the case where the qubit is being weakly…

Quantum Physics · Physics 2012-11-09 Srinivas Sridharan

This article provides a review of recent developments in the formulation and execution of optimal control strategies for the dynamics of quantum systems. A brief introduction to the concept of optimal control, the dynamics of of open…

Quantum Physics · Physics 2009-10-06 Robert Roloff , Markus Wenin , Walter Pötz

The ability to characterise a Hamiltonian with high precision is crucial for the implementation of quantum technologies. In addition to the well-developed approaches utilising optimal probe states and optimal measurements, the method of…

Quantum Physics · Physics 2022-12-14 Shushen Qin , Marcus Cramer , Christiane P. Koch , Alessio Serafini

We apply advanced methods of control theory to open quantum systems and we determine finite-time processes which are optimal with respect to thermodynamic performances. General properties and necessary conditions characterizing optimal…

Quantum Physics · Physics 2018-08-01 Vasco Cavina , Andrea Mari , Alberto Carlini , Vittorio Giovannetti

We propose an analysis of the time-optimal control of a dissipative two-level quantum system whose dynamics is governed by the Lindblad equation. This simple system allows one to use tools of geometric control theory and to construct its…

Quantum Physics · Physics 2007-08-29 D. Sugny , C. Kontz , H. R. Jauslin

Finding minimal time and establishing the structure of the corresponding optimal controls which can transfer a given initial state of a quantum system into a given target state is a key problem of quantum control. In this work, this problem…

Quantum Physics · Physics 2025-02-21 L. V. Lokutsievskiy , A. N. Pechen , M. I. Zelikin

Cooling of a quantum system is limited by the size of the control forces that are available (the "speed" of control). We consider the most general cooling process, albeit restricted to the regime in which the thermodynamics of the system is…

Quantum Physics · Physics 2015-06-05 X. Wang , Sai Vinjanampathy , Frederick W. Strauch , Kurt Jacobs

Open Markovian quantum systems with fast and full Hamiltonian control can be reduced to an equivalent control system on the standard simplex modelling the dynamics of the eigenvalues of the density matrix describing the quantum state. We…

Quantum Physics · Physics 2025-03-04 Emanuel Malvetti , Frederik vom Ende , Gunther Dirr , Thomas Schulte-Herbrüggen

We investigate the time-optimal control of the purification of a qubit interacting with a structured environment, consisting of a strongly coupled two-level defect in interaction with a thermal bath. On the basis of a geometric analysis, we…

Quantum Physics · Physics 2019-03-13 Jonas Fischer , Daniel Basilewitsch , Christiane P. Koch , Dominique Sugny

Implementing fast and high-fidelity quantum operations using open-loop quantum optimal control relies on having an accurate model of the quantum dynamics. Any deviations between this model and the complete dynamics of the device, such as…

Quantum Physics · Physics 2024-10-31 Elie Genois , Noah J. Stevenson , Noah Goss , Irfan Siddiqi , Alexandre Blais

We consider finite-dimensional Markovian open quantum systems, and characterize the extent to which time-independent Hamiltonian control may allow to stabilize a target quantum state or subspace and optimize the resulting convergence speed.…

Quantum Physics · Physics 2015-03-17 Francesco Ticozzi , Riccardo Lucchese , Paola Cappellaro , Lorenza Viola
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