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Related papers: Quantum Control at the Boundary

200 papers

We investigate optimal control strategies for state to state transitions in a model of a quantum dot molecule containing two active strongly interacting electrons. The Schrodinger equation is solved nonperturbatively in conjunction with…

Quantum Physics · Physics 2016-08-14 R. Nepstad , L. Sælen , I. Degani , J. P. Hansen

The computational treatment of many-electron systems capable of exchanging {electrons and nuclei} with the environment represents one of the outermost frontiers in simulation methodology. The exchanging process occurs in a large variety of…

Chemical Physics · Physics 2019-02-21 Luigi Delle Site

The challenging problems, in the field of control of chaos or of transition to chaos, lie in the domain of infinite-dimensional systems. Access to all variables being impossible in this case and the controlling action being limited to a few…

chao-dyn · Physics 2008-02-03 R. Vilela Mendes

The development of quantum control methods is an essential task for emerging quantum technologies. In general, the process of optimizing quantum controls scales very unfavorably in system size due to the exponential growth of the Hilbert…

Quantum Physics · Physics 2019-10-07 Jun Li

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

Recent advancements in quantum technologies have highlighted the importance of mitigating system imperfections, including parameter uncertainties and decoherence effects, to improve the performance of experimental platforms. However, most…

Quantum systems can be controlled by other quantum systems in a reversible way, without any information leaking to the outside of the system-controller compound. Such coherent quantum control is deterministic, is less noisy than…

Quantum Physics · Physics 2021-12-28 Thomas Konrad , Amy Rouillard , Michael Kastner , Hermann Uys

In recent years, analysis and control of quantum chaos are increasingly important, but the lack of the concept of trajectory makes it impossible to analyze quantum chaos by the methods used in classical chaos. This research aims to connect…

Quantum Physics · Physics 2022-04-01 Ciann-Dong Yang , Yen-Jiun Chen , Yun-Yan Lee

Methods of optimal control are applied to a model system of interacting two-level particles (e.g., spin-half atomic nuclei or electrons or two-level atoms) to produce high-fidelity quantum gates while simultaneously negating the detrimental…

A Markovian master equation describing the evolution of open quantum systems in the presence of a time-dependent external field is derived within the Bloch-Redfield formalism. It leads to a system--bath interaction which depends on the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 H. Jirari , W. Pötz

Limitations to the speed of evolution of quantum systems, typically referred to as quantum speed limits (QSLs), have important consequences for quantum control problems. However, in its standard formulation, is not straightforward to obtain…

Quantum Physics · Physics 2022-01-06 Pablo M. Poggi

One major objective of controlling classical chaotic dynamical systems is exploiting the system's extreme sensitivity to initial conditions in order to arrive at a predetermined target state. In a recent letter [Phys.~Rev.~Lett. 130, 020201…

Quantum Physics · Physics 2023-09-06 Steven Tomsovic , Juan Diego Urbina , Klaus Richter

A New theoretical formalism for the optimal quantum control has been presented. The approach stems from the consideration of describing the time-dependent quantum system in terms of the real physical observables, viz., the probability…

Chemical Physics · Physics 2015-06-26 Bijoy K. Dey

A systematic scheme is proposed to numerically estimate the quantum speed limit and temporal shape of optimal control in two-level and three-level quantum systems with bounded amplitude. For the two-level system, two quantum state…

Quantum Physics · Physics 2023-05-02 Xikun Li

The necessary time required to control a many-body quantum system is a critically important issue for the future development of quantum technologies. However, it is generally quite difficult to analyze directly, since the time evolution…

Quantum Physics · Physics 2024-11-21 Go Kato , Masaki Owari , Koji Maruyama

We give a rigorous argument that long--range repulsion stabilizes quantum systems; ground states of such quantum systems exist even when the ground state energy is precisely at the ionization threshold. For atomic systems at the critical…

Mathematical Physics · Physics 2020-12-24 Dirk Hundertmark , Michal Jex , Markus Lange

The dynamics near the top of a potential barrier is studied in the temperature region where quantum effects become important. The time evolution of the density matrix of a system that deviates initially from equilibrium in the vicinity of…

chem-ph · Physics 2009-10-28 Joachim Ankerhold , Hermann Grabert

By sending many two-level atoms through a cavity resonant with the atomic transition, and letting the interaction times between the atoms and the cavity be randomly distributed, we end up with a predetermined Fock state of the…

Quantum Physics · Physics 2007-05-23 M. Fortunato , G. Kurizki , W. P. Schleich

The success of quantum optimal control for both experimental and theoretical objectives is connected to the topology of the corresponding control landscapes, which are free from local traps if three conditions are met: (1) the quantum…

The control of individual quantum systems is now a reality in a variety of physical settings. Feedback control is an important class of control methods because of its ability to reduce the effects of noise. In this review we give an…

Quantum Physics · Physics 2017-08-01 Jing Zhang , Yu-xi Liu , Re-Bing Wu , Kurt Jacobs , Franco Nori