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Related papers: On estimation and feedback control of spin-1/2 sys…

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Feedback stabilization of an ensemble of non interacting half spins described by Bloch equations is considered. This system may be seen as a prototype for infinite dimensional systems with continuous spectrum. We propose an explicit…

Optimization and Control · Mathematics 2012-02-27 Karine Beauchard , Paulo Sergio Pereira da Silva , Pierre Rouchon

We present a formulation of measurement-based feedback control of a single quantum particle in one spatial dimension. An arbitrary linear combination of the position and momentum of the particle is continuously monitored, and feedback…

Quantum Physics · Physics 2022-12-26 Amy Rouillard , Anirudh Reddy , Humairah Bassa , Shamik Maharaj , Lajos Diosi , Thomas Konrad

We consider the evolution of a two-state quantum system (a spin 1/2 particle) in both the framework of standard quantum mechanics and under the decoherence regime. The former approach on this issue is the well-known quantum flipping process…

Quantum Physics · Physics 2011-07-21 Afshin Shafiee , Arash Tirandaz

We present an exact master equation for a central spin-$1/2$ system coupled to a spin-$1/2$ bath in terms of hyperfine interaction, which provides a unified formalism for both free evolution and controlled dynamics of the central spin. The…

Quantum Physics · Physics 2016-01-28 Jun Jing , Lian-Ao Wu

This paper is motivated by the problem of asymptotically stabilizing invariant sets in the state space of control systems by means of output feedback. The sets considered are smooth embedded in submanifolds and the class of system is…

Optimization and Control · Mathematics 2015-04-29 Christopher Nielsen

Information encoded in networks of stationary, interacting spin-1/2 particles is central for many applications ranging from quantum spintronics to quantum information processing. Without control, however, information transfer through such…

Quantum Physics · Physics 2018-07-31 Sophie G Schirmer , Edmond Jonckheere , Frank C Langbein

The finite-time control problem of quantum systems is investigated in this paper. We first define finite-time stability and present a finite-time Lyapunov stability criterion for finite-dimensional quantum systems in coherence vector…

Quantum Physics · Physics 2020-05-27 Sen Kuang , Xiaoke Guan , Daoyi Dong

We describe the formalism for optimally estimating and controlling both the state of a spin ensemble and a scalar magnetic field with information obtained from a continuous quantum limited measurement of the spin precession due to the…

Quantum Physics · Physics 2007-05-23 John K. Stockton , JM Geremia , Andrew C. Doherty , H. Mabuchi

Spin systems are one of the most promising candidates for quantum computation. At the same time control of a system's quantum state during time evolution is one of the actual problems. It is usually considered that to hold well-known…

Chaotic Dynamics · Physics 2007-09-05 L. Chotorlishvili , Z. Toklikishvili

Almost sure asymptotic stabilization of a discrete-time switched stochastic system is investigated. Information on the active operation mode of the switched system is assumed to be available for control purposes only at random time…

Systems and Control · Computer Science 2014-09-10 Ahmet Cetinkaya , Tomohisa Hayakawa

This paper presents convergence analysis of a novel data-driven feedback control algorithm designed for generating online controls based on partial noisy observational data. The algorithm comprises a particle filter-enabled state estimation…

Optimization and Control · Mathematics 2024-05-31 Siming Liang , Hui Sun , Richard Archibald , Feng Bao

In this work we analyze and bound the effect of modeling errors on the stabilization of pure states or subspaces for quantum stochastic evolutions. Different approaches are used for open-loop and feedback control protocols. For both, we…

Quantum Physics · Physics 2024-09-27 Weichao Liang , Kentaro Ohki , Francesco Ticozzi

In this paper we investigate parametrization-free solutions of the problem of quantum pure state preparation and subspace stabilization by means of Hamiltonian control, continuous measurement and quantum feedback, in the presence of a…

Quantum Physics · Physics 2016-11-17 Francesco Ticozzi , Kazunori Nishio , Claudio Altafini

This paper studies the feedback stabilization of abstract Cauchy problems with unbounded output operators by finite-dimensional controllers. Both necessary conditions and sufficient conditions for feedback stabilizability are presented. The…

Optimization and Control · Mathematics 2023-09-06 Tian Xia , Giacomo Casadei , Francesco Ferrante , Luca Scardovi

Precision control of a quantum system requires accurate determination of the effective system Hamiltonian. We develop a method for estimating the Hamiltonian parameters for some unknown two-state system and providing uncertainty bounds on…

The ultimate accuracy as regards controlling a qubit with a coherent field is studied in terms of degradation of the fidelity by employing a fully quantum mechanical treatment. While the fidelity error accompanied by pi/2 pulse control is…

Quantum Physics · Physics 2015-06-12 Kazuhiro Igeta , Nobuyuki Imoto , Masato Koashi

Measurement and feedback control are essential features of quantum science, with applications ranging from quantum technology protocols to information-to-work conversion in quantum thermodynamics. Theoretical descriptions of feedback…

Control using quantized feedback is a fundamental approach to system synthesis with limited communication capacity. In this paper, we address the stabilization problem for unknown linear systems with logarithmically quantized feedback, via…

Optimization and Control · Mathematics 2022-03-11 Feiran Zhao , Xingchen Li , Keyou You

The goal of quantum metrology is to improve measurements' sensitivities by harnessing quantum resources. Metrologists often aim to maximize the quantum Fisher information, which bounds the measurement setup's sensitivity. In studies of…

Feedback uses past detection outcomes to dynamically modify a quantum system and is central to quantum control. These outcomes can be stored in a memory, defined as a stochastic function of past measurements. In this work, we investigate…

Quantum Physics · Physics 2025-12-10 Alberto J. B. Rosal , Patrick P. Potts , Gabriel T. Landi