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Related papers: Quantum control by von Neumann measurements

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We tailor the quantum statistics of a bosonic field to deterministically drive a quantum system into a target state. Experimentally accessible states of the field achieve good control of multi-level or -qubit systems, notably also at…

Quantum Physics · Physics 2023-04-12 Frieder Lindel , Edoardo G. Carnio , Stefan Yoshi Buhmann , Andreas Buchleitner

Tests of quantum mechanics on a macroscopic scale require extreme control over mechanical motion and its decoherence. Quantum control of mechanical motion has been achieved by engineering the radiation-pressure coupling between a…

Quantum transport is the study of the motion of electrons through nano-scale structures small enough that quantum effects are important. In this contribution I review recent theoretical proposals to use the techniques of quantum feedback…

Mesoscale and Nanoscale Physics · Physics 2015-07-21 Clive Emary

We introduce an efficient iterative method to prepare a target state in Hilbert spaces with high dimensionality using a combination of unitary evolution, measurements, and quantum Zeno dynamics. The latter confines the evolution within Zeno…

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

The measurement process in quantum mechanics is usually described by the von Neumann projection postulate, which forms a basic constituent of the laws of quantum mechanics. Since this postulate requires the outside observer of the system,…

Quantum Physics · Physics 2009-11-11 Masahiro Morikawa , Akika Nakamichi

The ability to manipulate quantum systems lies at the heart of the development of quantum technology. The ultimate goal of quantum control is to realize arbitrary quantum operations (AQuOs) for all possible open quantum system dynamics.…

This paper explains some fundamental ideas of {\em feedback} control of quantum systems through the study of a relatively simple two-level system coupled to optical field channels. The model for this system includes both continuous and…

Quantum Physics · Physics 2014-06-23 Matthew James

A new approach to the problem of measurement in quantum mechanics is proposed. In this approach, the process of measurement is described in the Heisenberg picture and divided into two stages. The first stage is to transduce the measured…

Quantum Physics · Physics 2007-05-23 Masanao Ozawa

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 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

Quantum optimal control has numerous important applications ranging from pulse shaping in magnetic-resonance imagining to laser control of chemical reactions and quantum computing. Our objective is to address two major challenges that have…

Quantum Physics · Physics 2020-03-09 Jakub Marecek , Jiri Vala

We study the measurement-induced enhancement of the spontaneous decay (called quantum anti-Zeno effect) for a two-level subsystem, where measurements are treated as couplings between the excited state and an auxiliary state rather than the…

Quantum Physics · Physics 2013-07-12 Qing Ai , Dazhi Xu , Su Yi , A. G. Kofman , C. P. Sun , Franco Nori

We propose in this paper a gradient-type dynamical system to solve the problem of maximizing quantum observables for finite dimensional closed quantum ensembles governed by the controlled Liouville-von Neumann equation. The asymptotic…

Optimization and Control · Mathematics 2011-10-03 Ruixing Long , Herschel Rabitz

The higher than classical efficiency exhibited by some quantum algorithms is here ascribed to their non-mechanistic character, which becomes evident by joining the notions of entanglement and quantum measurement. Measurement analogically…

Quantum Physics · Physics 2007-05-23 Giuseppe Castagnoli , Dalida Monti

This paper discusses fully coherent quantum feedback control, in which the sensors, controller, and actuators are quantum systems and interact coherently with the system to be controlled: as a result, the entire feedback loop is coherent.…

Quantum Physics · Physics 2007-05-23 Seth Lloyd

The scope of this work is to provide a self-contained introduction to a selection of basic theoretical aspects in the modeling and control of quantum mechanical systems, as well as a brief survey on the main approaches to control synthesis.…

Quantum Physics · Physics 2012-10-29 Claudio Altafini , Francesco Ticozzi

Quantum measurements are crucial to observe the properties of a quantum system, which however unavoidably perturb its state and dynamics in an irreversible way. Here we study the dynamics of a quantum system while being subject to a…

In the ideal quantum Zeno effect, repeated quantum projective measurements can freeze the coherent dynamics of a quantum system. However, in the weak quantum Zeno regime, measurement back-actions can allow the sensing of semi-classical…

Von Neumann projections are the main operations by which information can be extracted from the quantum to the classical realm. They are however static processes that do not adapt to the states they measure. Advances in the field of adaptive…

Quantum Physics · Physics 2015-10-28 Amine Laghaout , Ulrik L. Andersen
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